information for parents

Misconceptions

Teaching science can be difficult because students have already formed ideas about the natural and designed world and how it works before coming to the classroom. An important factor influencing learning is identifying what preconceptions a learner has. A major challenge for science teachers is to build conceptual bridges from students' own ideas to scientifically accepted views. Once students' ideas have surfaced, making informed determinations about what can be done to move students toward the scientific view is the next step.

 

Misconceptions About

Misconceptions & Ideas to Watch Out For
About The Nature of Science

Scientific Method

Misconception: Scientists use the Scientific Method.

Misconception: Scientists must follow a linear step-by-step scientific method.

Misconception: Doing science requires little creativity.

Explanation: Real scientists use a large variety of methods (perhaps call them methods of science rather than "The Scientific Method.") Hypothesis / experiment / conclusion is one of these, and it's very important in experimental science such as physics and chemistry, but it's certainly not the only method. It would be a mistake to elevate it above all others. Close inspection will reveal that scientists approach and solve problems with imagination, creativity, prior knowledge and perseverance. These, of course, are the same methods used by all problem-solvers. Unlike the rigid "scientific method" most of us were taught when we were science students, scientists use their prior knowledge, novel questions, expectations, past experience, colleagues, creativity, and available funding and technology to help shape the procedures they use. Much of science does not, and cannot, rely on controlled experiments, yet it still provides solid conclusions regarding how the natural world works.

Misconception: A hypothesis is an educated guess.

Explanation: Science teachers have often simplified the meaning of the term "hypothesis" by describing a hypothesis as "an educated guess." Overemphasizing this aspect fails to convey the explanatory or predictive quality of scientific hypotheses. When students are asked to propose a hypothesis during a laboratory experience, they are being asked to make a prediction based on previous experience, observation and/or knowledge. A hypothesis refers to a provisional idea whose merit requires evaluation. For proper evaluation, the framer of a hypothesis needs to define specifics in operational terms. A hypothesis requires more work by the researcher in order to either confirm or disprove it. Any useful hypothesis will enable predictions by reasoning (including deductive reasoning). It might predict the outcome of an experiment in a laboratory setting or the observation of a phenomenon in nature.

Misconception: Not every activity in science is an "experiment."

Explanation: Use the term experiment when students are controlling variables, have a control group and are running tests to determine the influence of certain variables on a phenomenon. Otherwise, call it an investigation . This distinction is important because many scientists do not do experiments, yet they are still doing good science. Some of our students may not like experiments, and if they perceive that scientists only do experiments, they may begin to dislike science. In addition, some students may think that only experimental science is good science, and may then reject many science concepts that are not based on experimental work. Using terms carefully when teaching is important for teachers of all grades. However, teaching students the distinction between investigations and experiments is more appropriate above grade three.

Watch out for: Not every activity in science starts with a hypothesis.

Explanation: "Hypothesis testing" science is typically associated with an experimental setting, but a scientist making a hypothesis has a rich background that provides a foundation to make very informed judgments about what is to be expected. In fact, this expectation can cause the scientist to select some procedures over others, accept certain data while rejecting others, and favor certain kinds of explanations. When students are asked to make a hypothesis in a classroom setting, they very rarely have enough background knowledge to determine in advance what will occur. In addition, they are rarely given the opportunity to use their own ideas to inform the procedures that are used to investigate the phenomenon. When elementary teachers ask young children to make a hypothesis, what they unwittingly convey is that a hypothesis is a guess. When students make hypotheses under these conditions, they usually guess what the outcome will be, are frustrated when they are wrong, erase their original guess, and leave the experience feeling that science is difficult, unpredictable, or focused on right answers.

Misconception: Data tells scientists what to think.

Explanation: Data doesn't speak; instead, scientists have to develop an idea that makes sense of data. This is a crucial distinction! When we say to students, "What does the data tell you?" or "What do your observations show you?" we unwittingly send the message that the answers are right in front of the student. If this was the case, all students should come up with the same answer. The history of science is filled with examples of scientists looking at the same data but developing different explanations for those data. The important nature of science idea that science is a human endeavor means far more than people doing science - scientists are human and must wrestle with ideas and data that are not at all straightforward. Making sense out of the very messy natural world isn't easy for scientists, and it's not easy for our students. We can greatly help our students if we say, "What ideas do you have about this?" or "What do you think might be happening here?" Such phrasing enables students to feel more comfortable putting forward their ideas even when they may not be completely confident in those ideas. That's good scientific thinking! We can then use those tentative ideas to do further tests, discuss them with others, or try a new idea.

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Scientific Thinking

Misconception: Scientific knowledge changes primarily through invention of new technology.

Explanation: Although most students believe that scientific knowledge changes, they typically think changes occur mainly in facts and mostly through the invention of improved technology for observation and measurement. They do not recognize that changed theories sometimes suggest new observations or reinterpretation of previous observations. Some research indicates that it is difficult for middle-school students to understand the development of scientific knowledge through the interaction of theory and observation but the lack of long-term teaching interventions to investigate this issue makes it difficult to conclude that students can or cannot gain that understanding at this grade level.

Misconception: Hypotheses become theories which become laws.

Explanation: This myth deals with the general belief that with increased evidence there is a developmental sequence through which scientific ideas pass on their way to final acceptance. Many believe that scientific ideas pass through the hypothesis and theory stages and finally mature as laws. Theories and laws are very different kinds of knowledge. Of course there is a relationship between laws and theories, but one simply does not become the other--no matter how much empirical evidence is amassed. Laws are generalizations, principles or patterns in nature and theories are the explanations of those generalizations

Misconception: Knowledge in science is "proven" and "absolutely true."

Explanation: Avoiding the words prove and truth is an important way to accurately portray scientific knowledge. In science, we cannot ever know for certain that our ideas are absolutely correct. Moreover, we do not have access to all instances of a phenomenon in order to claim that our idea is "proven." While it is very easy to say "Prove it!" to a student, using such language conveys to our students that science is about proof. Instead of asking students to prove their ideas, ask students to find evidence for their ideas or support their ideas. K - 4 students are not yet ready to study the status of scientific knowledge, but not having the words prove and truth tied to science class will certainly help them later on when they learn why accepted scientific knowledge means those ideas are supported by a great deal of evidence and reasoning.

Watch out for : Inadequacies in arguments

Explanation: Most high-school students will accept arguments based on inadequate sample size, accept causality from contiguous events, and accept conclusions based on statistically insignificant differences. More students can recognize these inadequacies in arguments after prompting (for example, after being told that the conclusions drawn from the data were invalid and asked to state why.)

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Scientific Processes

Watch out for: Interpretation of data

Explanation: Students of all ages show a tendency to uncritically infer cause from correlation. Some students think even a single co-occurrence of antecedent and outcome is always sufficient to infer causality. Rarely do middle-school students realize the indeterminacy of single instances, although high-school students may readily realize it. Despite that, as covariant data accumulate, even high-school students will infer a causal relation based on correlations. Further, students of all ages will make a causal inference even when no variation occurs in one of the variables. For example, if students are told that light-colored balls are used successfully in a game, they seem willing to infer that the color of the balls will make some difference in the outcome even without any evidence about dark-colored balls.

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Watch out for: Manipulation and observation

Explanation: Upper elementary- and middle-school students who can use measuring instruments and procedures when asked to do so often do not use this ability while performing an investigation. Typically a student asked to undertake an investigation and given a set of equipment that includes measuring instruments will make a qualitative comparison even though she might be competent to use the instruments in a different context It appears students often know how to take measurements but not what or when.

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Numbers

Misconception: The use of calculators hinders the development of math skills.

Explanation: The use of calculators in K-12 mathematics does not hinder the development of basic computation skills and frequently improves concept development and paper-and-pencil skills, both in basic operations and in problem solving. The use of calculators in testing produces higher scores than paper-and-pencil efforts in problem solving as well as in basic operations.

Watch out for: Number comparison

Explanation: Lower elementary students do not have procedures to compare the size of whole numbers. By 4th grade, students generally have no difficulty comparing the sizes of whole numbers up to four digits. Students are less successful when the number of digits is much larger or when more than two numbers are to be compared. This might be due to increased memory requirements of working with more or larger numbers. Upper elementary- and middle-school students taught traditionally cannot successfully compare decimal numbers. Rather they overgeneralize the features of the whole number system to the decimal numbers. They apply a "more digits make bigger" rule (according to which .1814 > .385). After specially designed instruction which develops good meanings for decimal symbols, many students are able to compare decimal numbers with understanding by 5th grade. Upper elementary- and middle-school students taught traditionally cannot compare fractions successfully. Students' difficulties here indicate they treat the numerator and the denominator separately. Specially designed instruction to teach meanings for fractions can help to improve ordering fractions by as early as the end of the 5th grade.

Watch out for: Difficulties with orders of magnitude

Explanation: Studies have shown that students think that molecules of protein are bigger than the size of a cell. When referring to objects as being very small or very large, remember that these terms are relative to students. Provide students with comparisons to things that are smaller or larger.

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Misconceptions & Ideas to Watch Out For in Life Science

Organisms

Misconception: LIVING AND NONLIVING: Elementary- and middle-school students typically use criteria such as "movement," "breath," "reproduction," and "death" to decide whether things are alive. Thus, some believe fire, clouds, and the sun are alive, but others think plants and certain animals are nonliving.

Explanation: K-2 -Emphasis should be placed on examining a variety of familiar animals and plants and considering things and processes they all need to stay alive, such as food and getting rid of wastes. Most living things need water, food, and air. Some living things consist of a single cell. Like familiar organisms, they need food, water, and air; a way to dispose of waste; and an environment they can live in. All living things are composed of cells, from just one to many millions, whose details usually are visible only through a microscope. There are millions of different kinds of individual organisms that inhabit the earth at any one time-some very similar to each other, some very different.

Misconception: LIVING AND NONLIVING: High-school and college students also mainly use obvious criteria (e.g., "movement," "growth") to distinguish between "living" and "nonliving" and rarely mention structural criteria ("cells") or biochemical characteristics (" DNA "). It is suggested that the learning of facts has contributed little towards understanding. Students may be able to quote the seven characteristics of life, but unable to apply them.

Explanation: Organisms are composed of cells, the fundamental units of life. Some living things consist of a single cell. Like familiar organisms, they need food, water, and air; a way to dispose of waste; and an environment they can live in. All living things are composed of cells, from just one to many millions, whose details usually are visible only through a microscope.

Watch out for: LIVING AND NONLIVING: There are different views for "animal life" and "plant life." In general, animals were more often recognized as being alive than plants.

Explanation: Most living things need water, food, air, a way to dispose of waste, and an environment in which they can live.

Watch out for: Objects that are anthropomorphized are categorized as living.

Watch out for: WHEN CLASSIFYING ORGANISMS: Students in elementary and middle school tend to identify living organism based on grouping rather than hierarchy. EX: Because upper elementary-school students tend not to use hierarchical classification, they may have difficulty understanding that an organism can be classified as both a bird and an animal.

Similarities among organisms are found in internal anatomical features, which can be used to infer the degree of relatedness among organisms. In classifying organisms, scientists consider details of both internal and external structures. The degree of relatedness between organisms or species can be estimated from the similarity of their DNA sequences, which often closely match their classification based on anatomical similarities. Similar patterns of development and internal anatomy suggest relatedness among organisms. A classification system is a framework created by scientists for describing the vast diversity of organisms, indicating the degree of relatedness between organisms, and framing research questions.

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Life Cycle

Watch out for: LIFE CYCLE: K-8 students tend to equate life cycles only with the examples they observe in school, such as certain types of plant, butterfly, frog, or mealworm life cycles or organisms that are similar to those they studied. When students encounter organisms that are different from the ones they studied, they fail to recognize that all organisms have a life cycle.

Explanation: Plants and animals have life cycles that include being born, developing into adults, reproducing, and eventually dying.

Misconception: Once living things decay on their own accord or disappear.

Explanation: Decomposers, primarily bacteria and fungi, are consumers that use waste materials and dead organisms for food. One organism may scavenge or decompose another.

Misconception: Death is not a part of the life cycle.

Explanation: Plants and animals have life cycles that include being born, developing into adults, reproducing, and eventually dying. Death is the last stage of the life cycle. It represents when a living organism is no longer able to sustain life.

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Heredity

Watch out for: When asked to explain how physical traits are passed from parents to offspring, elementary-school, middle-school, and some high-school students express the following misconceptions: Some students believe that traits are inherited from only one of the parents (for example, the traits are inherited from the mother, because she gives birth or has most contact as children grow up; or the same-sex parent will be the determiner.)

Explanation: Every cell is covered by a membrane that controls what can enter and leave the cell. In all but quite primitive cells, a complex network of proteins provides organization and shape and, for animal cells, movement. Within the cells are specialized parts for the transport of materials, energy capture and release, protein building, waste disposal, passing information, and even movement. In addition to the basic cellular functions common to all cells, most cells in multicellular organisms perform some special functions that others do not. The work of the cell is carried out by the many different types of molecules it assembles, mostly proteins. Protein molecules are long, usually folded chains made from 20 different kinds of amino acid molecules. The function of each protein molecule depends on its specific sequence of amino acids and its shape. The shape of the chain is a consequence of attractions between its parts. The genetic information encoded in DNA molecules provides instructions for assembling protein molecules. The genetic information encoded in DNA molecules is virtually the same for all life forms.

Misconception: Other students believe that certain characteristics are always inherited from the mother and others come from the father. Some students believe in a "blending of characteristics." It may not be until the end of 5th grade that some students can use arguments based on chance to predict the outcome of inherited characteristics from observing those characteristics in the parents.

Explanation: Genes are segments of DNA that carry instructions for the traits of an organism. When organisms reproduce, genetic information from each parent is passed to the next generation. This passing of traits from parents to offspring is called heredity.

Watch out for: Early middle-school students explain inheritance only in observable features, but upper middle-school and high-school students have some understanding that characteristics are determined by a particular genetic entity which carries information translatable by the cell.

Explanation: When organisms reproduce, traits are passed from parent to offspring. These traits are carried in DNA , the genetic material found in a cell's nucleus. DNA acts like a blueprint for the cells of an organism, instructing them how to put together materials for produce certain traits.

Misconception: Students of all ages believe that some environmentally produced characteristics can be inherited, especially over several generations.

Explanation: Genes are segments of DNA that carry instructions for the traits of an organism. When organisms reproduce, genetic information from each parent is passed to the next generation. This passing of traits from parents to offspring is called heredity. The environment can influence an organism. EX: An organism's diet, state of health, and the amount of exercise it can get can change its body size and appearance.

Misconception: Many students tend to see adaptation as an intention by the organism to satisfy a desire or need for survival.

Explanation: Genes are segments of DNA that carry instructions for the traits of an organism. When organisms reproduce, genetic information from each parent is passed to the next generation. This passing of traits from parents to offspring is called heredity. The environment can influence an organism. EX: An organism's diet, state of health, and the amount of exercise it can get can change its body size and appearance. An organism cannot make cellular adaptations at will.

Misconception: Sexually produced offspring can be identical to either of their parents.

Explanation : This item specifically refers to "sexually" produced offspring rather than offspring produced via asexual reproduction, such as parthenogenesis, or other means. Sexually produced offspring are never identical to either of their parents. An egg and a sperm unite to begin development of a new individual. That new individual receives genetic information from its mother and its father.

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Cells

Watch out for : The familiar description and depiction of cells in blood sometimes lead students to the notion that organisms contain cells rather than that organisms are mostly made up of cells.

Explanation: All organisms are composed of cells, the fundamental units of life and the building blocks organisms. Most organisms are singlecells; other organisms, including humans, are multicellular. There are many different types of cells like heart cells, skin cells, blood cells, etc. They all have similar compartments including a nucleus that holds our genetic materials.

Watch out for : Imagining the large number of cells is also a problem for young children. Large organisms are composed of about a trillion cells, but this number means little to middle school students.

Watch out for : Students may have even more difficulty the idea that cells are the basic units in which life processes occur.

Explanation: Begin with the needs of macroscopic organisms verses with cell function. It is easier for students to understand that the cell is the basic unit of structure than the cell is the basic unit of function. This may be because the former is observable whereas the latter needs to be inferred from experiments.

Misconception: Students have difficulty differentiating between the concepts of cells and molecules. There is a tendency for students to over-apply the idea that cells are smaller components of living things.

Explanation: Cells have particular structures that underlie their functions. Every cell is surrounded by a membrane that separates it from the outside world. Inside the cell is a concentrated mixture of thousands of different molecules that form a variety of specialized structures.

Misconception: Oxygen is only for breathing.

Explanation: Another function of oxygen is that it is used by cells during respiration to break down sugars for energy.

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Interdependence

Watch out for : Students often think of organisms as independent of each other but dependent on people to supply them with food and shelter.

Explanation: Population size of a species has direct and indirect effects on both other species' populations and the environment, which in turn affects yet other species. From Munson 1994: "...people should understand that all organisms live in a system and that all changes are important and have effects on the system."

Plant "food" is a misnomer because mineral nutrients are not really food for plants. "Fertilizer" is the correct term.

Organisms interact with one another in various ways besides providing food.

Misconception: Upper elementary-school students may not believe food is a scarce resource in ecosystems; thinking that organisms can change their food at will according to the availability of particular sources.

Explanation: .the kinds of relationships that exist among organisms, the kinds of physical conditions that organisms must cope with, the kinds of environments created by the interaction of organisms with one another and their physical surroundings, and the complexity of such systems... For any particular environment, some kinds of plants and animals thrive, some do not live as well, and some do not survive at all.

Misconception: Students of all ages think that some populations of organisms are numerous in order to fulfill a demand for food by another population.

Explanation: Students should be able to define the carry capacity as the limit to the number of individuals of a species that a habitat can support. Students should be able to identify several limiting factors, including availability of food, shelter, and water, and the presence of predators. The supportable population of an organism, given the food, habitat, water and other necessities available within an environment is known as the environment's carrying capacity for that organism.

Misconception: Middle-school and high-school students may believe that organisms are able to effect changes in bodily structure to exploit particular habitats or that they respond to a changed environment by seeking a more favorable environment. It has been suggested that the language about adaptation used by teachers or textbooks to make biology more accessible to students may cause or reinforce these beliefs.

Explanation: Traits are genetically based and appear in individuals as a result of random processes. Natural selection influences the increasing or decreasing prevalence of traits in a population. So the degree and type of development of a trait depends on the genetic material available and the selective pressures in the environment over time.

Watch out for : Typically, the arrows of a food chain symbolize what each organism is eating (e.g., grass -> mouse -> snake -> hawk.)

Explanation : In a food chain, each organism represented, symbolizes a population of that type of organism. The first population makes up the first trophic level (plants or producers), the second is the next trophic level (consumers) and so on. The arrows point from one trophic level to the next, signifying the energy that is transferred between these trophic levels. The arrows may also be used to represent the flow of nutrients (or toxicants) in an ecosystem. However, many students interpret the arrows to mean that an organism is eating another organism and often believe that the arrows are therefore drawn incorrectly (backwards). According to the National Science Education Standards, students in grades 5-8 should understand that "Energy entering ecosystems as sunlight is transferred by producers into chemical energy through photosynthesis. That energy then passes from organism to organism in food webs." Students in grades 9-12 should understand that "energy flows through ecosystems in one direction, from photosynthetic organisms to herbivores to carnivores and decomposers."

Misconception : If the producers (plants) disappeared from Earth, organisms that prey on other organisms for food (carnivores) would only be slightly affected.

Explanation: If plants disappeared from Earth, the organisms that eat plants (e.g., herbivores) would begin to die. Gradually, carnivores that prey on herbivores would also start to die from lack of food. According to the National Science Education Standards, students in grades 5-8 should understand that "Populations of organisms can be categorized by the function they serve in an ecosystem. Plants and some micro-organisms are producers - they make their own food. All animals, including humans, are consumers, which obtain food by eating other organisms. Decomposers, primarily bacteria and fungi, are consumers that use waste materials and dead organisms for food. Food webs identify the relationships among producers, consumers, and decomposers in an ecosystem."

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Extinction

Watch out for: Extinction of species of organisms is common.

Explanation: Extinction of species is common; most of the species that have lived on earth no longer exist. The background level of extinction known from the fossil record is about one species per million species per year, or between 10 and 100 species per year (counting all organisms such as insects, bacteria, and fungi, not just the large vertebrates we are most familiar with). Current estimates, based on the rate at which the area of tropical forests is being reduced, and their large numbers of specialized species, are that we may now be losing 27,000 species per year to extinction from those habitats alone. Extinction of a species occurs when the environment changes and the adaptive characteristics of a species are insufficient to allow its survival. Fossils indicate that many organisms that lived long ago are extinct.

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Plants

Watch out for: Elementary- and middle-school students also hold a much more restricted meaning than biologists do for the word "plant." Students often do not recognize that trees, vegetables, and grass are all plants.

Explanation: Students need to be exposed to an assortment of plant types to build their understanding of plants.

Watch out for: 66% of students ages 10-14 do not believe a seed is alive.

Explanation: Seeds meet the criteria under living things. Seeds need to have their basic needs met such as having nutrients and air to survive. Seeds are the beginning stages of the life cycle.

Misconception: Most students think respiration and breathing are synonymous.

Explanation: Respiration takes place in all organisms with or without lungs or gills. It can also take place at a cellular level where it breaks down sugar for energy. Bacteria and fungi participate in anaerobic respiration. Respiration also happens in plants during photosynthesis.

Misconception: Plants do not need air to survive.

Explanation: All plants and animals need air in order to survive. Many people understand that animals need air and we know that humans must breathe in order to survive. Plants also need air. Plants use carbon dioxide from the air to make food through a process called photosynthesis. Plants also use oxygen found in the air in order to use the food energy that they have made.

Misconception: Plants do not use oxygen.

Explanation : Cellular respiration is a biochemical process that occurs in all cells. Plant cells use oxygen during cellular respiration. During photosynthesis plants use carbon dioxide and release oxygen. However plant cells also need oxygen in order to breakdown molecules of food to release energy used for building new cells. Some students incorrectly think that plants do a reverse type of human breathing - that is they take in carbon dioxide and release oxygen but do not utilize oxygen. In living organisms, oxygen is second only to hydrogen based on the number of atoms and oxygen is the largest constituent by mass. The National Science Education Standards state that plants require air, water, nutrients, and light. This helps to account for the fact that plants need carbon dioxide to make food and oxygen to utilize food.

Misconception: Seeds need light in order to grow.

Explanation: All plants need energy which they get from food. The seed already contains food energy that can help the plant to begin growing. When the food energy in the seed is used up then it must be able to obtain energy from another source. Plants can make their own food through a process called photosynthesis, but they need light in order for photosynthesis to happen. So a seed does not need light to begin growing because it already has a food (or energy source) stored in the seed. But once that is used up, than the plant must have light in order to make its own food. As long as the seed is exposed to moisture and the appropriate temperature range, it can begin using the food stored in the seed and it has all that is needed to begin growing.

Misconception: The only essential constituents that plants need in order to grow are: water, light, and nutrients from the soil or medium in which they exist. Although photosynthesis is recognized as a plant function, students still maintain the idea that plants obtain their food from their environment.

Explanation: Plants also need air to grow. Specifically, plants need carbon dioxide and oxygen from the air. The National Science Education Standards state that organisms have basic needs. Plants require air, water, nutrients, and light. Although most individuals understand that plants need water, nutrients (or soil), and light, many do not understand how and why plants need air. You may have provided another valid explanation as there are other requirements for some plants. However, many individual do not understand that specific gases are needed for plant growth.

Misconception: In order for a plant to grow, you need to provide the plant with fertilizer.

Explanation: Plants are capable of making their own food through the process of photosynthesis. Although plant fertilizer makes certain nutrients available to plants, unless the medium in which the plants are growing is completely sterile, plants will obtain the energy they need for growth from the food they produce.

Misconception: The only factors that are necessary for a plant seed to germinate (sprout) are water and certain temperature range.

Explanation: The seed contains a seed coat for protection, endosperm tissue for food, and the plant embryo. As long as the seed is exposed to moisture and the appropriate temperature range, it has all of the components needed to germinate. The embryo is able to obtain food from the endosperm tissue. As the embryo grows, the endosperm tissue is no longer essential because the sprouting plant begins to make its own food via photosynthesis.

Misconception: Celery stalk is a stem.

Explanation: The edible celery stalk is not a plant stem. It is a petiole, which is part of a leaf.

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Animals

Watch out for: Most students list only vertebrates as animals. Studies show that preservice elementary teachers, also hold restricted meanings for the concept of "animal." This may affect students' opportunities to learn the scientific view of animals.

Explanation: Biological classification at the kingdom level places more emphasis on cellular details, anatomical details, and embryology than on general appearance or behavior. Animals have body plans and internal structures that enable them to obtain their food from an external source, making them consumers or heterotrophs). Animal Kingdom can be split up into main groups, vertebrates (with a backbone) and invertebrates  (without a backbone). When you think of an animal, you usually think of something like a cat, a dog, a mouse, or a tiger. All told, around 800,000 species have been identified in the Animal Kingdom -- most of them in the Arthropod phylum. In fact, some scientists believe that if we were to identify all species in the tropical rain forests the ranks of Arthropoda would swell to over 10 million species!  Most people do not normally think of a clam, a jellyfish, or an earthworm as an animal. 

Watch out for: A study of 15-year-olds found that 10% identified animals as a biologist would from an assortment of organisms. Typically, people of all ages have a much narrower definition of animal than biologist.

Explanation: A great variety of kinds of living things can be sorted into groups in many ways using various features to decide which things belong to which group. Biological classification at the kingdom level places more emphasis on cellular details, anatomical details, and embryology than on general appearance or behavior. Animals have body plans and internal structures that enable them to obtain their food from an external source, making them consumers (or heterotrophs).

Watch out for: Humans are often not thought of as animals; rather they are contrasted with animals. Humans, insects, birds, and fish are often thought of as alternatives other than animals, not as subsets of animals.

Explanation: A great variety of kinds of living things can be sorted into groups in many ways using various features to decide which things belong to which group. Biological classification at the kingdom level places more emphasis on cellular details, anatomical details, and embryology than on general appearance or behavior. Animals have body plans and internal structures that enable them to obtain their food from an external source, making them consumers or heterotrophs).

Misconception: Children think animals grow or stretch to accommodate the food they eat.

Explanation: People obtain energy and materials from food for body repair and growth. Some source of energy is needed for all organisms to stay alive and grow. Food and other materials are transformed and taken into the body, thus making it bigger.

Misconception:: If a living thing can move on its own then scientists call it an animal.

Explanation: Scientists currently classify living organisms into six kingdoms, but the two we tend to know the best are plants and animals. The five kingdoms are: (1) Archebacteria (2) Eubacteria (3) Protista (4) Fungi (4) Plantae (Plants) (6) Animalia (Animals). Scientists have found that some organisms classifed as Archeabacteria, Eubacteria or Protista, in addition to Animals, may move on their own.

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Misconceptions & Ideas to Watch Out For in Earth Science

Geology

Misconception: We live on the flat middle of the sphere.

Explanation: Earth itself is not flat. Earth is roughly spherical or ball shaped, but its shape is not perfect. Earth is a little flattened at its poles and bulges a bit at its equator. The Earth's features on its surface vary from mountain ranges to valleys to oceans and more, which may lead children to believe it is flat in some places. Another reason is that the sky above surrounds us and meets us at the horizon; therefore, it appears that we are on the flat part.

Misconception: Molten earth material (magma) that produces such features as volcanoes comes from the middle mantle (about half way between the Earth's center and surface.)

Explanation: Magma forms in the earth's mantle. The magma that reaches the earth's surface is formed just below the lithosphere, not as deep as the middle mantle. Because liquid magma is less dense than the surrounding solid material, magma will flow upward. It flows into any cracks in the rock above it. Magma rises until it reaches the surface and then we call it lava. It also may become trapped beneath layers of rock. According to the National Science Education Standards, students in grades 5-8 should understand that "The solid earth is layered with a lithosphere, hot, convecting mantle; and dense, metallic core." They should also understand that "Lithospheric plates on the scales of continents and oceans constantly move at rates of centimeters per year in response to movements in the mantle. Major geological events, such as earthquakes, volcanic eruptions, and mountain building, result from these plate motions."

Watch out for: There is a 10% chance that Chicago will experience a powerful earthquake (greater than 5.0 on the Richter scale) in the next 50 years.

Explanation: In the United States , the risk for severe earthquakes is highest along the Pacific coast, because that is where the Pacific and North American plates meet. However, even east of the Rockies , the region has experienced some of the most powerful quakes in the nation's history. Scientists hypothesize that the plate forming most of North America is under stress and this stress could disturb faults that formed millions of years ago causing major earthquakes. Less than 200 years ago Chicago experienced a major earthquake and it is not unlikely that this could happen again in the near future. The New Madrid fault system stretches beneath the central Mississippi River valley (approximately 400 miles south of Chicago ). Scientists estimate that there is a 90 percent chance that a moderate earthquake will occur in this area in the next 50 years. According to the National Science Education Standards, students in grades 5-8 should understand that "Lithospheric plates on the scales of continents and oceans constantly move at rates of centimeters per year in response to movements in the mantle. Major geological events, such as earthquakes, volcanic eruptions, and mountain building, result from these plate motions."

Watch out for: Some students have a landform and ocean basin conception that involves a progressively decreasing slope from the center of the continents to the center of the bottom of the ocean and then back up again.

Explanation: There are many landforms on the surface of the earth including under the ocean. The ocean has mountains, valleys, and volcanoes and many other physical features as above the surface.

Watch out for: Students often think of mountain building as occurring only through catastrophic events such as earthquakes or volcanoes. They often fail to recognize the slow process of uplift over millions of years.

Explanation: Interactions among the solid Earth, the oceans, the atmosphere, and organisms have resulted in the ongoing evolution of the Earth system. We can observe changes such as earthquakes and volcanic eruptions on a human time scale, but many processes such as mountain building and plate movements take place over hundred of millions of years.

Watch out for: Earth and space science have a unique aspect of scale that may be problematic for students. For example, comprehending the length of time it takes for mountains to erode is difficult for some students.

Watch out for: Students have a variety of ideas about the composition of mountains and their formation. Children describe mountains as "high rocks" or "clumps" of dirt or soil. Most children are unable to use a theory of mountain building involving the theory of plate tectonics.

Explanation: Interactions among the solid Earth, the oceans, the atmosphere, and organisms have resulted in the ongoing evolution of the Earth system. We can observe changes such as earthquakes and volcanic eruptions on a human time scale, but many processes such as mountain building and plate movements take place over hundred of millions of years.

Watch out for: Dirt is not the same as soil.  Soil comes from rivers, volcanic action, or was there since Earth formed.

Explanation: Soil is made of tiny pieces of rock, minerals, and decayed plant and animal matter. The tiny pieces of rock and the minerals came from large rocks that were weathered. This cycle occurs over time on Earth.

Watch out for: The distinction between natural things and those created by humans. For example, some students considered brick a rock because it is made of natural material. Conversely, some students thought cut, smooth, polished marble is not a rock because humans made it smooth so it is no longer natural.

Misconception: Many students think rocks are of a particular size than characterized by what they are made of. Therefore, some students believe that rocks are larger, heavier, and jagged and identify smaller fragments as stones instead of rocks.

Explanation: Chunks of rocks come in many sizes and shapes, from boulders to grains of sand and even smaller. Rock is composed of different combinations of minerals. Smaller rocks come from the breakage and weathering of bedrock and larger rocks.

Watch out for: Some children often fail to recognize that words like boulder, gravel, sand, and clay have specific meanings related to the average size of fragments. For example, children think of clay as being sticky, orange stuff found underground rather than a very fine particle of rock.

Explanation: Chunks of rocks come in many sizes and shapes, from boulders to grains of sand and even smaller. Rock is composed of different combinations of minerals. Smaller rocks come from the breakage and weathering of bedrock and larger rocks.

Misconception:The amount of fresh water on Earth is more than 3%.

Explanation: Of all the water on earth, approximately 97% is found in the oceans and only about 3% is fresh water. Of the fresh water, only a fraction is available for humans to use. Thus, of all the water on earth, less than 1% is usable by humans. This statement can be confused with the percentage of the earth's surface that is covered by water (71%) as opposed to land (29%). If you were looking for a percentage in this range, you may have been thinking about how much water there is compared to land rather than where we find the water that does exist (mostly in the oceans). Students should be aware that although water is plentiful on Earth, usable water is limited. According to the National Science Education Standards, students in grades 9-12 should understand that "the earth does not have infinite resources; increasing human consumption places severe stress on the natural processes that renew some resources, and it depletes those resources that cannot be renewed."

Misconception: Fossils are actual preserved animals or plant parts.

Explanation: Fossils are remains, impression, track, traces, or other evidence of organism that lived long ago.

Misconception: Fossils cannot tell us about the environment in which plants or animals lived long ago.

Explanation: The relative position of fossils within layers of rock provides a record of the geologic events occurring at a place. For instance, when marine fossils are found at a site, it means that at one time seas covered the land.

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Atmosphere

Misconception: Winds are primarily responsible for driving ocean currents.

Explanation: Surface ocean currents are caused by two factors: Coriolis Effect and wind. This only affects large bodies of water such as oceans. Subsurface currents in oceans happen because of differences in density. Density differences result from temperatures and salinity differences. When colder, saltier, denser water meets less dense water, the denser water dives under the less dense water.

Misconception: Wind speed is related to temperature of air - high speed means cold air and gentle or slow winds are warm.

Explanation: The difference between high pressure and low pressure causes wind speed. The greater the difference in air pressure, the faster the wind speed.

Misconception: Weather changes from season to season, but not day to day.

Explanation: Weather changes from day to day and over the seasons. Weather can be described by things we measure such as temperature, wind direction, wind speed, and precipitation. Each day these measurements of weather change and we see general patterns of change from season to season.

Misconception: Humid air is heavier than dry air.

Explanation: Imagine a cubic foot of perfectly dry air. It contains about 78% nitrogen molecules, which each have a molecular weight of 28. Another 21% of the air is oxygen, with each molecule having a molecular weight of 32. The final one percent is a mixture of other gases, which we won't worry about. What Avogadro discovered leads us to conclude that if we added water vapor molecules to our cubic foot of air, some of the nitrogen and oxygen molecules would leave - remember, the total number of molecules in our cubic foot of air stays the same.

The water molecules, which replace nitrogen or oxygen, have a molecular weight of 18. This is lighter than both nitrogen and oxygen. In other words, replacing nitrogen and oxygen with water vapor decreases the weight of the air in the cubic foot; that is, it's density decreases. But, the water that makes the air humid isn't liquid. It's water vapor, which is a gas that is lighter than nitrogen or oxygen.

Misconception: Heat and temperature mean the same thing.

Explanation: Heat is a form of energy. As something is heated it is gaining more energy. This energy may be stored energy which we call "potential energy" or energy of motion which we call "kinetic energy". Temperature is what we use to measure the kinetic energy of the substance. So most times when something is heated its temperature also increases so we tend to think of heat and temperature as the same thing. However sometimes a substance can be heated but the temperature does not increase because the heat energy increases the potential energy instead. For example, ice and liquid water can both exist at a temperature of 0 degrees Celsius (or 32 degrees Fahrenheit). Even though the temperature is the same, the liquid water has more potential energy than the ice.

Misconception: Rain comes from clouds' sweating.

Explanation: The atmosphere contains water vapor. When air gets cooler, water vapor condenses. That means it changes to tiny droplets of liquid water. Water droplets clump together to form a cloud. As more water vapor condenses, the droplets grow larger. When the droplets get too large and heavy they fall to the Earth's surface.

Misconception: Rain comes from holes in clouds.

Explanation: The atmosphere contains water vapor. When air gets cooler, water vapor condenses. That means it changes to tiny droplets of liquid water. Water droplets clump together to form a cloud. As more water vapor condenses, the droplets grow larger. When the droplets get too large and heavy they fall to the Earth's surface.

Misconception: Clouds move because we move.

Explanation: Objects in the sky have patterns of movement. Clouds move with the wind. High cirrus clouds are pushed along by the jet stream, sometimes traveling at more than 100 miles-per-hour. When clouds are part of a thunderstorm they usually travel at 30 to 40 mph.

Misconception: Clouds are "sponges" that hold water or bags of water than rain when they are shaken by wind or perhaps when they become cold or hot.

Explanation:The atmosphere contains water vapor. When air gets cooler, water vapor condenses. That means it changes to tiny droplets of liquid water. Water droplets clump together to form a cloud. As more water vapor condenses, the droplets grow larger. When the droplets get too large and heavy they fall to the Earth's surface.

Misconception: A visible cloud in the sky consists primarily of water vapor.

Explanation: Clouds form when water vapor in the air becomes liquid water or ice crystals. As the air temperature decreases, water vapor in the air condenses. Tiny particles must be present on which the water vapor condenses. When water droplets or ice crystals form on these small particles they stay suspended in the air and appear as various types of clouds. According to the National Science Education Standards, students in grades 5-8 should understand that "Clouds, formed by the condensation of water vapor, affect weather and climate."

Misconception: Air as a substance is not well understood.  Air has negative weight or no weight.

Explanation: Air is a substance that surrounds us, takes up space, and whose movement we feel as wind. Air is made up of a mixture of gases. Air has mass; therefore, air has weight.

Misconception: On a hot, humid day you place a cold glass of lemonade on the table. The droplets of water you notice forming on the outside of the glass are due primarily to condensation of water vapor from the surrounding air.

Explanation: Water vapor in the air is water in the gaseous state. These water molecules are moving fast and have very little attraction for each other. As a water molecule in the gaseous state comes into contact with the cold surface of the glass, it may lose energy and move slower. It may lose so much energy that it becomes water in the liquid state. The process of changing from a gas to a liquid is called condensation. As molecules of water slow, their attractive forces increase. Thus slower molecules are attracted to other water molecules on the glass or also to the surface of the glass. Small droplets of water form from condensed water vapor in the surrounding air. According to the National Science Education Standards, students in grades K-4 should understand that "Materials exist in different states - solid, liquid, and gas. Some common materials, such as water, can be changed from one state to another by heating or cooling."

Misconception: Water vapor is held or soaked up by the air.

Explanation: Water vapor enters the air when liquid water on Earth's surface is evaporated. Most water vapor comes from Earth's oceans, lakes, and rivers. Some comes from damp soil. Some comes from plants and animals.

Misconception: As one goes higher into the atmosphere (for example, climbing a mountain), the atmospheric pressure does not decrease.

Explanation: Air pressure is the result of the weight of a column of air pushing down on an area. As one goes higher into the atmosphere, the amount of air "above" the person has decreased, thus the air pressure also decreases. Other factors also affect the air pressure. When there is more moisture in the atmosphere, it means that water molecules (H2O) have replaced other kinds of molecules that are heavier (e.g., N2 or O2) and therefore more moisture indicates lower density or lower air pressure. As the air pressure decreases, the density of the air also decreases. So density decreases as altitude increases. According to the National Science Education Standards, students in grades 5-8 should understand that "the atmosphere has different properties at different elevations."

Misconception: A baseball hit with the same force will NOT travel farther on a humid day as opposed to a dry day, assuming the baseball maintains its properties of elasticity and mass independent of the weather conditions.

Explanation: On humid days there is more moisture in the air. When there is more moisture in the atmosphere, it means that water molecules (H2O) have replaced other kinds of molecules that are heavier (e.g., N2 or O2). This makes the mass of the air less per unit area, therefore decreasing the density of the air. More moisture in the air indicates lower density or lower air pressure. Thus, the baseball hit on a humid day will be traveling through air that is less dense and will travel farther. This seems to be very counterintuitive because on humid days, we often believe that the air feels "heavy" or more dense. This is partially because evaporation of our sweat is decreased on humid days, making us feel "sticky" or like the air is heavy. To understand this, students need a more sophisticated understanding of atmospheric pressure and effects of moisture and temperature on the air around us. However, in reality the baseball itself is also affected by these conditions which can change these results.

Misconception: Air pollution is always caused by human activities.

Explanation: Some human activities contribute to air pollution, but not all air pollution comes from people. The following are some natural events that cause air pollution.

  • Dust from natural sources, usually large areas of land with little or no vegetation.
  • Methane , emitted by the digestion of food by animals , for example cattle .
  • Radon gas from radioactive decay within the Earth's crust.
  • Smoke and carbon monoxide from wildfires .
  • Volcanic activity, which produce sulfur, chlorine and ash particulates .

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Astronomy

Misconception: There is a definite up and down in space.

Explanation : It is all relative, but even on earth it's not perfect. Think about this: A person on the north pole points "up" to the sky. For another person at the south pole person to truly be pointing in the same direction they would have to be pointing "down" towards the ground. That example aside, we normally think of up and down on a smaller regional scale, so that "up" is towards the sky RELATIVE to wherever on earth you are at that moment.
So why is there no up and down in space? Only because there's no universally standard frame of reference. In theory scientists could all agree on some arbitrarily determined points X, Y, and Z accesses... but it just wouldn't be as obvious as the ground you're standing on.

Misconception: The Earth's revolution around the sun causes night and day.

Explanation: There are two important movements that affect the Earth. The first is the rotation of the Earth around an invisible axis. It takes the Earth about 24 hours to finish one complete rotation. This motion is responsible for days and nights (because every time shows to the Sun a different side of the Earth). The second important movement that affects the Earth is its revolution around the Sun. One revolution takes 365 ¼ days, or one year. Acting together, these two movements create variations in temperature, weather, and in the seasons.

Watch out for: What causes day and night?

Explanation: Only half of the earth is illuminated by the sun at any given time. This half is lit by the sun (day) and the other half is dark (night). The Earth's spinning on its axis is called rotation. The Earth's axis is an imaginary line that passes through Earth's center and the North and South poles. The Earth's rotation on its axis causes day and night. As Earth rotates eastward, the sun appears to move westward across the sky. Student in Grades K-4 should understand that, "The sun, moon, stars, clouds, birds, and airplanes all have properties, locations, and movements that can be observed and described. Objects in the sky have patterns of movement. The sun, for example, appears to move across the sky in the same way every day, but its path changes slowly over the seasons ."

Misconception: From homes in the continental United States , there is a date or time when the sun is directly overhead.

Explanation: In the continental United States , even at noon , the sun is always to the south. In the Northern Hemisphere, the noon sun is directly overhead at 23.5 degrees north around June 21st, called the summer solstice. However, latitudes in the continental United States are far north of this position and thus the sun is never directly overhead. Seasons result from variations in the amount of the sun's energy hitting the surface, due to the tilt of the earth's rotation on its axis and the length of the day. Also, according to the National Science Education Standards, students in grades K-4 should begin to understand that "objects in the sky have patterns of movement. The sun, for example appears to move across the sky in the same way every day, but its path changes slowly over the seasons."

Misconception: Seasons are caused by the Earth's distance from the Sun.

Explanation: This is by far the most common misconception about the relationship between Sun and Earth, one that is unfortunately perpetuated by lousy diagrams in most school textbooks. When someone says we are closer to the Sun in the summertime, do you ever remind them that while it may be summer in the northern hemisphere, it is wintertime in the southern hemisphere...and six months from now, the seasons and Earth's position will be reversed? In fact, in summer in the northern hemisphere, Earth is actually at its farthest point away from the Sun. So how can that be?

Despite what you learned in school about Earth's "elliptical" orbit around the Sun, that elliptical orbit is pretty close to being circular (not the extended oval you see in most books). The change of seasons is mainly the result of the tilt of Earth's invisible spin axis, which is inclined 23.5 degrees in comparison to the axis of the Sun. Sometimes Earth's axis is tilted toward the Sun and sometimes away from it -- and somewhere in between for the rest of the year. It is this tilt ­ combined with the motion of the Earth around the Sun ­ that causes more or less light to fall on one hemisphere or the other during each of the seasons. This means that the amount of sunlight falling directly on a parcel of Earth changes throughout the year. It also means that days get longer or shorter, causing the Sun to warm part of the Earth for longer and shorter periods of each day.

Misconception: It is colder in the winter because the Earth is further away from the Sun and warmer in the summer because Earth is closer to the Sun.

Explanation: When someone says we are closer to the Sun in the summertime, do you ever remind them that while it may be summer in the northern hemisphere, it is wintertime in the southern hemisphere...and six months from now, the seasons and Earth's position will be reversed? In fact, in summer in the northern hemisphere, Earth is actually at its farthest point away from the Sun. So how can that be?

Despite what you learned in school about Earth's "elliptical" orbit around the Sun, that elliptical orbit is pretty close to being circular (not the extended oval you see in most books). The change of seasons is mainly the result of the tilt of Earth's invisible spin axis, which is inclined 23.5 degrees in comparison to the axis of the Sun. Sometimes Earth's axis is tilted toward the Sun and sometimes away from it -- and somewhere in between for the rest of the year. It is this tilt ­ combined with the motion of the Earth around the Sun ­ that causes more or less light to fall on one hemisphere or the other during each of the seasons. This means that the amount of sunlight falling directly on a parcel of Earth changes throughout the year. It also means that days get longer or shorter, causing the Sun to warm part of the Earth for longer and shorter periods of each day.

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Moon

Misconception: The moon can only be seen at night.

Explanation: You can see the Moon in the daytime because it is big and brightly lit by the Sun. The surface of the Moon is about as reflective as an asphalt road--rather dark but not totally black. When you look at the Moon, you are seeing the light which reflects off it. The region of the sky containing the Moon is much brighter, so you can see it. You can also sometimes see Venus during the day if the conditions are right and you know exactly where to look, but anything dimmer is lost.

Misconception: Clouds cover part of the Moon, planets casts shadows on the moon, the shadow of the Sun falls on the moon, and the shadow of the Earth falls on the Moon.

Explanation: Understanding the moon phases may be challenging to students until they reasonably grasp ideas about the Earth, Moon, and Sun system, including relative size, distance, and motion. Most objects in the solar system are in regular and predictable motion. Those motions explain such phenomena such as the day, year, phases of the moon, and eclipses. The observable shape of the Moon changes from day to day in a cycle that lasts about a month. The Moon orbits the earth is about 28 days which changes the part of the Moon lit by the Sun. Therefore, changes which part of the moon we can see from Earth as phases of the Moon.

Misconception: The Moon does not rotate on its axis as it revolves around the earth.

Explanation: Like the earth, the moon rotates on its axis.

Misconception: Phases of the Moon are caused by a shadow from the Earth.

Explanation: Phases of the moon are caused by the relative positions of the moon, Earth, and the sun. The sun lights the moon and it is always only half lit. Since the moon revolves around Earth, we see the moon from different angles and see fractions of the portion of the moon that is lit. The phase of the moon you see depends on how much of the sunlit side of the moon faces your position on Earth. According to the National Science Education Standards, students in grades K-4 should begin to understand that "objects in the sky have patterns of movement. . . The observable shape of the moon changes from day to day in a cycle that lasts about a month."

Watch out for : Different countries see different phases of the Moon on the same day.

Explanation: The Moon phase we see is due to the relative positions of the Earth, Moon, and Sun. The Moon is always half illuminated by the Sun. From Earth we see fractions of the lit Moon, which we view as phases. When people in North America see a full Moon, they are seeing the full side of the lighted portion of the Moon. The Earth also rotates and people in Australia would see the same phase as those who live in North America . However, for phases such as a first quarter, the side on which the Moon appears to be lit will be the opposite. This means that first quarter would look different, depending on your viewpoint from Earth.

Watch out for: The Moon goes around the earth in a single day.

Explanation: It takes 27.322 days for the moon to go around Earth.

Misconception: The Moon makes light the same way the Sun does. The moon emits its own light, rather than reflecting light from the sun.

Explanation: You can see the Moon because it is big and brightly lit by the Sun. The surface of the Moon is about as reflective as an asphalt road--rather dark but not totally black. When you look at the Moon, you are seeing the light which reflects off it. This is not nearly as bright as the Sun, but it is up to 100,000 times as bright as the brightest nighttime star.

Misconception: One side of the Moon is always dark.

Explanation: The term "dark side of the Moon" is really a misnomer, because the side that we are familiar with is dark just as frequently. A better term might be "far side of the Moon. "The orbit of the Moon is such that one rotation is just about as long as one revolution in its orbit around the Earth. Because of this, one side is facing us during its orbit. However, this side is often dark. During a "new moon", the moon is between the Earth and the Sun, and so the side we know is totally dark. When the moon is opposite from the Sun, the side we know will be totally bright, and the far side will be dark.

Misconception: An astronaut is standing on the moon with a baseball in her/his hand. When the baseball is released, it will NOT fall to the moon's surface.

Explanation: The moon, or any object with mass, exerts a gravitational attraction to other objects with mass. Gravitation is a universal force that each mass exerts on any other mass. The strength of the gravitational attractive force between two masses is proportional to the masses and inversely proportional to the square of the distance between them. While the gravitational force would not be as strong as on earth, because the moon is not as massive as earth, it still exists.

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Sun

Misconception: The Sun does not rotate.

Explanation: Like almost everything else in our clockwork universe, the Sun rotates around an invisible axis. The rotation of the Sun was actually one of Galileo's greatest discoveries. By observing sunspots moving across the face of the Sun, Galileo figured out that it wasn't just the spots that were moving, but the whole star. It takes an average of 27 days for the Sun to make a full rotation, though the rate is actually about 25 days at the equator and as many as 32 days near the Sun's poles. This "differential" rotation ­ where the equator spins faster than the poles -- is perhaps the leading cause of the magnetic mayhem on the Sun that leads to sunspots, flares, and coronal mass ejections.

Misconception: The Sun is directly overhead at noon.

Explanation: The sun, for example, appears to move across the sky in the same way every day, but its path changes slowly over the seasons. Sometimes it can be difficult to notice these changes unless you carefully observe its position under the same conditions. For example, you will notice these changes if you observe the sun's position at the same time each day, from the same location, with the same surroundings for a frame of reference.

Misconception: The surface of the sun does not have any visible features.

Explanation: The photosphere can be seen with the naked eye. With a simple telescope and a proper filter one can look at sunspots, granules, and faculae.

Misconception: The Sun has a solid surface.

Explanation: The Sun is made entirely of gas, so there isn't a fixed, solid surface. The part that looks like the surface -- the photosphere -- is simply the region of gas on the edge of the Sun that emits light in wavelengths that we can see.

Misconception: The Sun Moves up and down and When we watch the sun during the day, it seems to move across the sky. Its path across the sky doesn't change from day to day.

Explanation: Objects in the sky have patterns of movement. However, someone should never stare directly at the sun because it is not safe to do so. The sun, for example, appears to move across the sky in the same way every day, but its path changes slowly over the seasons. Sometimes it can be difficult to notice these changes unless you carefully observe its position under the same conditions. For example, you will notice these changes if you observe the sun's position at the same time each day, from the same location, with the same surroundings for a frame of reference.

Misconception: The Sun will never burn out.

Explanation: No. Stars are born, live, and die. This process is called the "life cycle of a star". Most of the time a star shines, it is in a stage of its life cycle called the main sequence. How long it stays in the main sequence phase depends on how much mass the star has. Our Sun is a little over 5 ½ billion years old. It is believed it is in the middle of its life span.

Misconception: Sunspots are dark and cool.

Explanation: True and False- We now know that sunspots really are huge regions of magnetic field, about as intense as the field at the poles of an iron magnet. For some reason the field slows down the flow of heat from the Sun's interior and keeps sunspots slightly cooler than their surroundings. Sunspots are locations on the Sun where extremely strong magnetic fields have cooled the hot plasma (electrically charged gas) to slightly less than that of the surrounding regions. They are actually footprints of active regions where enormous loops of magnetic force trap plasma within them in the corona (atmosphere) of the Sun. The plasma in these magnetic loops is heated to the point that it gives off ultraviolet light.

Misconception: The sun rises exactly in the east and sets exactly in the west every day.

Explanation: Earth rotates or spins toward the east, and that's why the Sun, Moon, planets, and stars all seem to rise in the east and make their way westward across the sky. Suppose you are facing east - the planet carries you eastward as it turns, so whatever lies beyond that eastern horizon eventually comes up over the horizon and you see it! The Earth's revolution around the Sun changes the position of the Sun in the sky; therefore, the Sun does not set and rise in the exact same place all year.

Misconception: Auroras are caused by solar wind particles hitting Earth's atmosphere.

Explanation: Not really. Auroras are caused by particles (mostly electrons) being guided by Earth's magnetic field into the atmosphere, where they bounce off and collide with air molecules. These collisions give energy to the air molecules. To release that excess energy, the air molecules (mostly oxygen and nitrogen) emit the light that we call an aurora. But the electrons that cause auroras do not come directly from the Sun. At the beginning of the Space Age, scientists discovered that the space around Earth is filled with plasmas (hydrogen electrons and protons) trapped by our planet's magnetic field. These particles are collected over long periods of time from the solar wind, or they have leaked out of our own atmosphere. When a solar storm erupts, the impact of the event can distort and energize Earth's magnetic field. Some of this energy energizes the particles already trapped around Earth, causing them to slide down those field lines into Earth's upper atmosphere, to smash into the gas of the atmosphere, and to release photons of light.

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Solar System and Universe

Misconception: Planets appear in the sky in the same place every night.

Explanation: Planets change their position against the background of stars. Planets revolve around the Sun like Earth. Add their revolution and our revolution around the Sun and the planets appear in different places in our night sky.

Misconception: Space is empty, a complete vacuum.

Explanation: Space is filled everywhere by plasma, a fourth state of matter (solid, liquid, gas, and plasma). Plasma is a gas in which electrons have been separated from their atoms (ions), making it electrically charged. Plasma is extremely rare on Earth; you can only find it in candle flames, lightning, and fluorescent lights. But in fact, 99% of the universe is made up of plasma. Of course, space is so vast that all this plasma gets spread out to a point where it seems like a vacuum by our earthly standards.

Misconception: The Universe is a static, not expanding.

Explanation: On the basis of scientific evidence, the universe is estimated to be over ten billion years old. There were early periods in the universe's history before stars were formed and the process of star formation and destruction continues as the universe expands. The expanding Universe is finite in both time and space . The universe is in a constant state of change. Hubble noted that galaxies outside our world were moving away from us, each at a speed proportional to its distance from us. He quickly realized that this meant that there must have been an instant in time when the entire Universe was contained in a single point in space.

Misconception: The Universe contains only the planets in our solar system.

Explanation: We are one of many solar systems in our galaxy. The universe contains billions of galaxies, and each galaxy contains billions of stars.

Misconception: The earth is the center of the solar system and is the largest object in the solar system. 

Explanation: The Sun is the center of our solar system and the largest object in our solar system. Our solar system is one of billions in the universe. Earth is not in the center.

Misconception: There is no gravity in space .

Explanation: There is gravity in space, but it is not the same as the gravitational pull you feel on Earth.

Misconception: The total mass + energy in the universe is constantly changing.

Explanation: The total mass + energy of the universe is constant. Energy can be transferred by collisions in chemical and nuclear reactions, by light waves and other radiations, and in many other ways. However, it can never be destroyed.

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Stars

Misconception: Stars and constellations appear in the same place in the sky every night.

Explanation: The position of the constellations changes with the seasons since Earth is revolving around the Sun.

Misconception: Stars cannot be seen during the day, because they are on the opposite side of the Earth where it is night time or that the stars set at night as the Sun does.

Explanation: The pattern of stars during an evening stays the same but their location overhead, relative to where the you are viewing them as the Earth rotates during a 24-hour period, changes. The light of the Sun during the day makes it difficult to see the stars.

Misconception: All the stars in a particular constellation are near each other.

Explanation: The stars in the galaxy are scattered around our solar system and the universe. The distance from star to star varies.

Misconception: Because all stars are the same size, the brightness of a star depends only on its distance from earth.

Explanation: Star sizes range from dwarf to giant sized. The distance of each star varies as some are further away than others. The Sun is many thousands of times closer to Earth than any other star. Light from the Sun takes a few minutes to reach Earth, but light from the nearest star takes a few years to arrive.

Misconception: Stars are evenly distributed through a galaxy or throughout the universe. All stars are the same distance from the Earth.

Explanation: There are more stars in the sky than anyone can easily count, but they are not scattered evenly, and they are not all the same brightness or color. The distance of each star from the Earth is different.

Misconception: There are stars dispersed throughout our solar system.

Explanation: Our solar system contains one star, the Sun. The stars seen on Earth are stars in other galaxies.

Misconception: Moon and sun are about the same size.  Stars are smaller than sun or moon.

Explanation: The moon is closer to the Earth than the Sun, so it appears to be the same size. But the Sun is the largest body in our Solar system and the Earth is larger than the moon. The stars appear to be smaller than the moon because the moon is closer than the nearest star which is not in our solar system.

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Misconceptions & Ideas to Watch Out For In Physical Science

Properties of Matter

Misconception: Gases are not matter.

Misconception: Matter is something that can be handled and takes up space.

Misconception: Energy is an ingredient in matter.

Explanation: All matter is made up of particles (e.g., atoms or molecules); has weight and mass; takes up space (has volume); and exists in the forms of solid, liquid, gas or plasma. In order to be considered matter, an object, material, or substance must meet these characteristics.

Elementary and middle-school students may think everything that exists is matter, including heat, light, and electricity. Alternatively, they may believe that matter does not include liquids and gases or that they are weightless materials. With specially designed instruction, some middle-school students can learn the scientific notion of matter. Although some 3rd graders may start seeing weight as a fundamental property of all matter, many students in 6th and 7th grade still appear to think of weight simply as "felt weight"-something whose weight they can't feel is considered to have no weight at all. Accordingly, some students believe that if one keeps dividing a piece of styrofoam, one would soon obtain a piece that weighed nothing.

Misconception: Matter is continuous.

Misconception; The space between particles is filled.

Misconception: Expansion of matter is due to the expansion of particles, rather than an increase of particle spacing.

Explanation: Middle-school and high-school students are deeply committed to a theory of continuous matter. Many students think the space between gas particles is non-existent or filled, or that particles expand when they are heated. Although some students may think that substances can be divided up into small particles, they do not recognize the particles as building blocks, but as formed of basically continuous substances under certain conditions. Students at the end of elementary school and beginning of middle school may be at different points in their conceptualization of a "theory" of matter.

Misconception: Living systems are made of cells not molecules.

Explanation: Studies have shown that students confuse cells with molecules. When asked whether certain things were made of cells and/or molecules, things that were living or once living were designated as being made of cells but not molecules. Even molecules studied in biology such as carbohydrates and proteins were thought to be made up of cells, not molecules. A molecule is formed when two or more atoms join together by sharing electrons to form a larger particle. Not all matter is made of molecules. Matter can also exist as metals and ionic crystalline lattice structures, depending how the bonds between atoms form. There is a hierarchy of arrangement from subatomic particles to atoms to molecules to substances. Context is a factor in this misconception. In biology students learn about various molecules necessary for life but may fail to recognize that cells and cell structures are made up of molecules.

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States of Matter

Watch out for: There are more than three states of matter.

Explanation: There are five states of matter including plasma and Bose-Einstien condensates, but students are primarily asked to classify substances as solids, liquids and gases. Direct sensory experience leads children to a naive view of matter involving more than three states. Children think of metals and wood as typical solids. To them, substances which are not hard and rigid cannot be solids, so classifying solids which do not "fit" this image is difficult. Many children classify non-rigid solids such as dough, sponge, sand and sugar separately from coins, glass or chalk. As a result, children create additional states of matter.

Misconception: When water boils, the bubbles we see are mostly air.

Explanation: The liquid water molecules are gaining energy and are becoming water vapor. Water vapor is water in the gaseous state

Misconception: Dissolving and melting are the same thing.

Explanation: Although two materials are required for the dissolving process, children tend to focus on the solid and regard the process as melting. Both processes can be gradual which adds to the misconception. Melting is a process in which a solid undergoes changes in the arrangement and average motion of particles to become a liquid. In order to melt, a substance needs to absorb heat energy. This heat energy increases the average motion of the particles, resulting in a change of state. Dissolving is not a change of state. When solid materials dissolve they involve intermolecular forces that help break down substances into smaller particles (such as molecules or ions). Dissolving requires two materials to be mixed together (solvent and solute).

Misconception: The white substance coming from boiling water is smoke.

Misconception: When the steam is no longer visible it becomes air.

Misconception: Steam is hot air.

Misconception: Hydrogen and oxygen which separated during boiling recombine to form water in the air.

Explanation: The gas escaping from boiling water is water vapor. When this vapor condenses in the air it is visible as tiny water droplets.

Misconception: Water in an open container is absorbed by the container.

Misconception: Water in an open container disappears.

Misconception: Water in the open container changes into air or disappears and turns into air. 

Misconception: The water dries up - it is not steam, it just dries up and goes into the air.

Explanation: Water left in an open container evaporates, changing from liquid to gas.

Misconception: Condensation on the outside of a container is water that seeped through the container itself (or sweated through the walls of the container.)

Misconception: The coldness comes through the container and produces water.

Misconception: Condensation is when air turns into a liquid.

Explanation: Condensation is water vapor in the air which cools sufficiently to become a liquid. This usually happens when the water vapor comes in contact with a (cool) surface. d.

Misconception: Gases are not matter because they are invisible. 

Misconception: Gas has no weight - even if it has color it has no weight. 

Misconception: Gases weigh less than the materials that created them. 

Misconception: Air neither has mass nor can it occupy space.

Misconception: When gases expand more gas is present.

Explanation: Gases, like other matter, have mass and take up space. The amount of gas in a closed container is constant but the volume can change as pressure changes.

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Density

Misconception: For an object to float it must contain air.

Misconception: Heavy things sink; light things float.

Misconception: Flat things float.

Misconception: Hard things sink; soft things float.

Misconception: A large amount of water will make things float.

Explanation: Density describes how much mass is in a given volume of material. Solids, liquids and gases all have density. An object sinks if its density is greater than that of the liquid it is submerged into. It floats if its density is less than that of the liquid. Use counterevidence to confront students' misconceptions. For example a student may believe heavy things sink and light things float because a boulder will sink and leaf will float in water. Counterevidence for this might be that a large log will float in water as does a small stick or a boulder will sink as does a pebble.

Misconception: The mass of an ice cube is changed after it melts.

Misconception: When the shape of something is changed, the mass is changed.

Misconception: When a bulk solid is changed into a powdered solid, there is a decrease in mass.

Explanation: Conservation of matter is a physical principle that applies to physical and chemical changes in substances. Students cannot understand conservation of matter and weight if they do not understand what matter is, or accept weight as an intrinsic property of matter, or distinguish between weight and density. By 5th grade, many students can understand qualitatively that matter is conserved in transforming from solid to liquid. They also start to understand that matter is quantitatively conserved in transforming from solid to liquid and qualitatively in transforming from solid or liquid to gas-if the gas is visible. For chemical reactions, especially those that evolve or absorb gas, weight conservation is more difficult for students to grasp. Lower elementary students fail to conserve weight and volume of objects that change shape.

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Interactions of Matter

Misconception: When a chemical reaction occurs, the total mass of the resulting products can be less than or greater than the original mass of the reactants depending on the type of chemical reaction that took place.

Explanation: One of the fundamental laws involving chemistry that is taught in school is the Law of Conservation of Matter. This law states that matter can neither be created nor destroyed by chemi­cal reactions. The mass of the products of a reaction must equal the mass of the reactants. Howev­er, sometimes it seems as if mass has disappeared, particularly when one or more of the products is a gas. For example, think about the mass of a sheet of paper before it is burned. Once it is burned, the ashes seem to have much less mass. In this type of reaction, gases are produced, which have mass but are not observed easily. Another example, if seeds, a moist paper towel and air are sealed in a jar, then the seeds begin to sprout many students will believe the mass of the system will increase. When in fact, due to the law of conservation of matter the mass remains unchanged.

Misconception: Particles can change form.

Explanation: Students ascribe macroscopic properties to particles. For example, particles may explode, burn, contract, expand and / or change shape. This primitive reasoning prohibits understanding of the nature of a chemical reaction.

Misconception: Misunderstanding chemical changes.

Explanation: Middle- and high-school student thinking about chemical change tends to be dominated by the obvious features of the change. For example, some students think that when something is burned in a closed container, it will weigh more because they see the smoke that was produced. Further, many students do not view chemical changes as interactions. They do not understand that substances can be formed by the recombination of atoms in the original substances. Rather, they see chemical change as the result of a separate change in the original substance, or changes, each one separate, in several original substances. For example, some students see the smoke formed when wood burns as having been driven out of the wood by the flame.

Misconception: Rusting causes a decrease in mass.

Explanation: Students often think rusting is a change in which mass decreases, due to an intuitive notion of rusting being similar to a decay process. Rusting is an example of oxidation - a chemical change in which electrons from the iron atoms are transferred to the oxygen atoms, resulting in the formation of a new compound. The oxygen in the air chemically combines with the iron. As a result the additional mass from the oxygen is added to the mass of the iron that is rusting to form a new compound, iron oxide. Although the appearance of the metal makes it look as if it is "breaking down," it is actually gaining mass as it changes from iron to iron oxide. If the metal were kept in a closed system and the mass determined was that of the total system, then conservation of mass would be observed and the mass would not change.

Misconception: If a small amount of sugar is added to a closed container of water allowed to sit for a long period of time without stirring, the sugar molecules will be more concentrated at the bottom of the container.

Explanation: The water molecules are in continuous motion and act as a solvent for the small amount of sugar that is added to the container. Individual sugar molecules become surrounded by water and are pulled away from the original sugar crystal. Because the molecules are in constant motion, they will become evenly distributed throughout the solution.

Misconception: When things dissolve they "disappear."

Explanation: For example, when sugar is dissolved in lemonade, the visible sugar substance breaks down into sugar molecules. The sugar molecules cannot be seen, so it appears to have "disappeared", but it is there. The total mass of the sugar and lemonade before and after the dissolving is the same as explained by the law of conservation of matter.

Misconception: Compounds with ionic bonds behave as simple molecules.

Explanation: Students see the formulas of ionic bonds written as "NaCl" or "MgCl 2 ". There is no distinction between these formulas and "CH 4 " or "H 2 O", which are mainly covalent compounds. The three-dimensional structure of compounds with mainly ionic bonding is ignored. Although this is chemical convention, students learning chemistry need help to realize that compounds with mainly ionic bonds behave differently from those with covalent bonds. For example, understanding that ions separate when a mainly ionic compound dissolves in a solvent, rather than the "molecule" staying together.

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Physics

Air Pressure

Misconception: Vacuums "suck" or pull things into them. 

Misconception: An evacuated (crushed) can or deflated bike tire has less pressure inside than out. 

Misconception: Vacuums cannot exist as nearby air will rush in to fill it.

Explanation: Vacuums are areas of low (or zero) pressure. Areas of high pressure will push against the walls of a vacuum to equalize the pressure.

Misconception: Many students believe that blowing on something always makes it move away. 

Misconception: Some students believe that blowing takes the pressure with it.

Explanation: Blowing creates areas of faster moving air which has a lower air pressure. High pressure areas will cause motion into the areas of low pressure.

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Energy

Misconception: Energy is a fluid which flows between places and/or objects. It is human dependent.

Explanation: Energy is a measure of a system's capacity to do work. Energy has several forms.

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Electricity

Misconception: When two bulbs are wired in series, the first bulb is brighter because it 'uses up' the current first.

Explanation: Many students will use a source-consumer model in which the battery gives something to the bulb. When two bulbs are wired in series both bulbs will be equally bright. A single bulb in a circuit will be brighter that two bulbs in a series circuit.

Watch out for: Difficulty making a bulb light when provided with a battery and wires.

Explanation: Studies show that, before instruction, many k-8 students are not aware of the bipolarity of batteries and lightbulbs. They do not recognize the need for a complete circuit and have difficulty making a bulb light when provided with a battery and wires. Even high school and university students have shown difficulty with this task. The battery, wire and bulb need to be connected in such a way that it forms a complete circuit. To do this, hold the end of the wire against the negative terminal (the bottom of the battery or smooth end). The other end of the wire should touch or wrap around the side of the metal casing that forms the base of the lightbulb. With the wire wrapped around the metal side of the bulb and the other end touching the bottom of the battery, touch the tip of the base of the lightbulb to the positive terminal and the bulb will light.

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Waves & Sound

Misconception: Sound can be produced without using any materials.

Misconception: Hitting an object harder changes the pitch of the sound produced.

Explanation: Sound is produced by vibrating objects. Vibrations can be thought of as a "back and forth" movement. Sometimes these vibrations are not noticeable, but it is still happening. Sometimes the matter that is vibrating cannot be seen (like vibrations of air molecules). If you lightly touch your throat while you are talking or humming, you can feel these vibrations. If you change the sound that you make, the vibrations will feel different. The pitch of a sound can be varied by changing how fast the object is vibrating. The slower the vibration the lower the pitch. The faster the vibration the higher the pitch. The speed of the vibrations is called frequency. The loudness of the sound depends on the size of the vibrations. The size of the vibrations is called amplitude. The harder an object is hit the louder the sound.

Misconception: Sound can travel through a vacuum, such as space.

Misconception: Sounds cannot travel through solids and liquids.

Watch out for: Sound travels better through solids?

Explanation: Sound is produced by vibrations. We hear the sound when our ear receives the vibrating air molecules. Sound waves require a medium to travel. Therefore, no sound is transmitted through a vacuum. Sound waves can travel through solids, liquids and gases. Sound travels through most liquids and solids faster than through air. "Faster" doesn't mean "better." This is because sound is a traveling vibration (oscillation) and depends on restoring forces. The forces holding steel atoms together are much stronger than the forces between the molecules in air. Stronger restoring forces raise the speed of sound.

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Light & Color

Misconception: Color is a property of an object rather than reflected light off an object.

Misconception: A color filter adds color to a white beam.

Explanation: Light from the sun is made up of a mixture of many different colors of light, even though to the eye the light looks almost white. A prism can be used to separate white light into the colors that make it up. Color is how we perceive the energy of light. All the colors of the rainbow are light of different energies. Red light has the lowest energy and violet light has the highest energy. An object appears red because the red light waves are reflected. This means that all the other colors are absorbed. Similar to a color filter. A red filter over a flashlight lens allows only the red light wave to pass through and absorbs all the other colors. White is a reflection of all the colors and black is the absence of color, so all the colors are being absorbed. This is why a white shirt feels cooler on a hot summer day than a black shirt.

Misconception: Light helps us see simply by illuminating objects and making them visible.

Misconception: While light is reflected by mirrors, it remains on other objects.

Explanation: To see an object, light from that object (either emitted by or reflected from it) must enter the eye. Although our eyes can adjust to very dark environments, it is when an object interacts with light that we are able to see it. Light waves reflected off an object must enter our eye in order for us to see it. Light exists between our eyes and the object we are viewing. Light travels in a straight line until it strikes an object where it is then reflected, refracted or absorbed by the object.

Misconception: Infrared is "heat radiation", not light. 

Misconception: Infrared is the only type of light that, when absorbed, causes objects to heat. 

Watch out for: Infrared light is not a kind of heat.

Explanation: Infrared light is bright but invisible light. When light of any sort is absorbed by an object the object gets heated.

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Heat & Temperature

Misconception: Heat rises.

Explanation: Heat does not rise. Heat cannot rise. Heat is not even a thing that could be seen even if it could rise. Heat is a form of energy. When some students finally come to realize that heat is not a thing that can rise, they modify the statement to say "Hot objects rise." This is not necessarily true either. A hot rock will sink in a cool lake. A hot space capsule sinks through the air. An ice cube floats in warm water. So this explanation is not sufficient either. To be correct, the statement should read, "Less dense materials float in fluids that are denser than they are." Then, the explanation for a hot air balloon is that the balloon is less dense than the surrounding air, so it floats. What's even more beautiful about this is that the same explanation can be used for a helium balloon, a fishing bobber, an iceberg, or the Titanic . . . ok, maybe not the Titanic, but some other large ship. To understand the distinction, it will be necessary for students to have been taught previously how temperature affects density. But when these two concepts are taught separately, a clear understanding is possible. When they are combined together, they become confused. To crush this misconception, have students put hot rocks in cold water and put an ice cube in warm water to see a hot object sinking and a cold object floating.

Misconception: Hot air rises.

Explanation: Heat does not rise. Heat cannot rise. Heat is not even a thing that could be seen even if it could rise. Heat is a form of energy. When some students finally come to realize that heat is not a thing that can rise, they modify the statement to say "Hot objects rise." This is not necessarily true either. A hot rock will sink in a cool lake. A hot space capsule sinks through the air. An ice cube floats in warm water. So this explanation is not sufficient either. To be correct, the statement should read, "Less dense materials float in fluids that are denser than they are." Then, the explanation for a hot air balloon is that the balloon is less dense than the surrounding air, so it floats. What's even more beautiful about this is that the same explanation can be used for a helium balloon, a fishing bobber, an iceberg, or the Titanic . . . ok, maybe not the Titanic, but some other large ship. To understand the distinction, it will be necessary for students to have been taught previously how temperature affects density. But when these two concepts are taught separately, a clear understanding is possible. When they are combined together, they become confused. To crush this misconception, have students put hot rocks in cold water and put an ice cube in warm water to see a hot object sinking and a cold object floating.

Misconception: Atoms get bigger when you heat them up.

Explanation: When matter is heated it expands because the molecules are vibrating more quickly, loosening bonds, and increasing the space between adjacent atoms or molecules.

Misconception: Temperature & heat are the same thing.

Explanation: Students very commonly believe that temperature and heat is exactly the same thing. Temperature and heat are not the same thing. An object can have high temperature and very little heat. An object can also have very low temperature and a lot of heat. Temperature (average kinetic energy) is simply how fast molecules are moving in an object like billiard balls on a pool table. Heat is a form of energy (thermal) that depends on the temperature as well as the type of molecule, and how many molecules in the object. Temperature is measured with a thermometer. Heat cannot be measured directly.

A good analogy for temperature versus heat was on a science cartoon series called Eureka . They asked "Which would you rather have, a cup full of 100-dollar bills or a swimming pool filled with 1-dollar bills?" The value of an individual bill represents temperature and the total dollar value represents heat. Although the temperature in the cup is higher, the heat in the swimming pool is greater. By looking at the swimming pool, you could tell the metaphorical temperature, but you cannot tell how much heat there is. This helps show why temperature is directly measurable and heat is not. You can tell how fast molecules are moving, but there is no device that can simultaneously measure the temperature of the molecules, the type of molecule and how many molecules there are.

Misconception: Sweat cools you off the same way pouring cold water on you.

Explanation: Many students believe that sweat cools you down because water is cool. But sweat comes out at exactly the same temperature as your skin, maybe even a little hotter. It is not cool. So, how does it cool you then? It cools through evaporation. You've probably heard that steam burns worse than hot water. This is not a misconception, it is true. It takes heat to boil water and it gives that energy back when it condenses. It also takes heat to evaporate water. In the case of sweat, the heat to evaporate the sweat comes from you. Your skin gives it the energy that it needs to evaporate and then it takes that energy with it. This also helps to explain why it feels so much hotter on a humid day. When there is a lot of water in the air, sweat does not evaporate well. It stays on your skin and does nothing. The water that some students think is so cool does not cool you at all when it cannot evaporate. On humid days, students are covered by sweat and it does not cool them.

Misconception: An object at 0 degrees has no heat.

Explanation: Many students believe that because the freezing point of water is 0 o C that all ice is at that temperature. But 0 o C is simply the maximum possible temperature for ice under normal conditions. If your freezer is set to -4 o C, then the ice cubes will be -4 o C. If it is -24 o C in Siberia , then the snow and ice there are at -24 o C. It is true that a glass of ice water is usually at 0 o C. When you put ice cubes into a drink, the cubes cool down the drink by absorbing heat energy from the drink. As the ice cubes warm up, the drink cools down. Normally, there is more drink than there is ice. So the cubes go up to 0 o C and then begin to melt. So once the cubes have been sitting in the

drink for a couple of minutes, the entire drink will very likely be at 0 o C. The same is true for ice that has been sitting out of the freezer for a few minutes. It will absorb heat energy from the air until it reaches 0 o C and then begin to melt.

Misconception: Heat acts as a fluid.

Misconception: Heat is a substance which can be added to or removed from an object.

Explanation: Heat is a form of energy. This energy (thermal energy) can be transferred from one object to another. When objects absorb thermal energy their temperature increases.

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Motion

Misconception: For every action there is an equal and opposite reaction.

Explanation : Newton originally published his laws of motion in Latin, and in the English translation, the word "action" was used in a different way than it's usually used today. It was not used to suggest motion. Instead it was used to mean "an acting upon." It was used in much the same way that the word "force" is used today. What Newton 's third law of motion means is this:

For every FORCE applied, there must be an equal FORCE in the opposite direction; Whenever any object A exerts a force on any other object B, object B exerts an equal but opposite force on A.

Or in modern terms...

For every FORCE applied, there must be an equal FORCE in the opposite direction.

So while it's true that a skateboard does fly backwards when the rider steps off it, these motions of "action" and "reaction" are not what Newton was investigating. Newton was actually referring to the fact that when you push on something, it pushes back upon you equally, even if it does not move. When a ball is resting on the floor in the classroom, it is pushing down on the floor.  The floor is pushing up on the ball. That is a good illustration of Newton 's third Law. Newton 's Third Law can be rewritten to say:

For every force there is an equal and opposite force.

Or "you cannot touch without being touched." Or even simpler: Forces always exist in pairs.

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Forces

Misconception: Friction is caused by surface roughness.

Explanation: Some books point to surface roughness as the explanation of sliding friction. Surface roughness merely makes the moving surfaces bounce up and down as they move, and any energy lost in pushing the surfaces apart is regained when they fall together again. Friction is mostly caused by chemical bonding between the moving surfaces; it is caused by stickiness. Even scientists once believed this misconception, and they explained friction as being caused by "interlocking asperites", the "asperites" being microscopic bumps on surfaces. But the modern sciences of surfaces, of abrasion, and of lubrication explain sliding friction in terms of chemical bonding and "stick & slip" processes. The subject is still full of unknowns, and new discoveries await those who make surface science their profession.

Misconception: If a body is not moving there is no force, and if something is moving, there is a force acting on it.

Explanation: When something is not moving it does not mean that forces are not acting on it. When something is not moving it may be a case of forces that are balanced with each other. In the case of a book on a table, gravity is acting on the book in one direction and the table can be thought of as "pushing back" and therefore the book remains still. The forces in the table that "push back" come from the bonds between the atoms that make up the table material. A force is a push or a pull. The position and motion of objects can be changed by pushing or pulling. The size of the change is related to the strength of the push or pull. An object that is not being subjected to a force will continue to move at a constant speed and in a straight line.

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