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What is a physical change?

Back

A physical change is a change that affects one or more physical properties of a substance without altering its chemical composition. Examples include changes in state (like melting or freezing), shape, or size.

Front

Which of the following is NOT a physical change?

Back

A gas forming is NOT a physical change; it indicates a chemical change.

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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.

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What is an exothermic reaction?

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An exothermic reaction is a chemical reaction that releases energy to its surroundings, usually in the form of heat.

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What is temperature?

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Temperature is a measure of the average energy of random motion of particles in a substance.

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What is thermal energy?

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Thermal energy is the total energy of all the particles in an object, which is related to its temperature.

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What happens to the energy during a physical change?

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During a physical change, the energy may change forms (like heat energy during melting) but the substance's chemical identity remains the same.

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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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Can a physical change be reversed?

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Many physical changes can be reversed, such as freezing and melting, but some may not be easily reversible.

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What is an example of a physical change?

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Examples of physical changes include tearing paper, melting ice, and dissolving sugar in water.