Chemical and Physical Changes Flashcard

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What is an endothermic reaction?

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An endothermic reaction is a chemical reaction that absorbs energy from its surroundings, usually in the form of heat. An example is photosynthesis in plants.

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What is a physical change?

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A physical change is a change that affects one or more physical properties of a substance without altering its chemical composition. An example is the freezing of water.

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How does the energy of products compare to reactants in an endothermic reaction?

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In an endothermic reaction, the energy of the products is higher than that of the reactants.

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What is a chemical change?

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A chemical change is a process that involves the transformation of one or more substances into different substances, characterized by changes in chemical properties. An example is the rusting of iron.

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What is a sign of a chemical change?

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A sign of a chemical change can include a change in color, the formation of a gas, or the production of heat.

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What is combustion?

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Combustion is a chemical reaction that occurs when a substance reacts rapidly with oxygen, producing heat and light. An example is the burning of gasoline.

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What is the difference between a physical change and a chemical change?

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A physical change alters the form or appearance of a substance without changing its chemical composition, while a chemical change results in the formation of new substances.

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What is photosynthesis?

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Photosynthesis is the process by which green plants use sunlight to synthesize foods with the help of chlorophyll, converting carbon dioxide and water into glucose and oxygen.

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What happens during the rusting of iron?

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Rusting of iron is a chemical change where iron reacts with oxygen and moisture in the environment to form iron oxide, commonly known as rust.

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What is the significance of energy changes in chemical reactions?

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Energy changes in chemical reactions indicate whether a reaction is endothermic (absorbs energy) or exothermic (releases energy), which affects reaction rates and equilibrium.