Physical and Chemical Changes Review

Front

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 melting, freezing, and dissolving.

Front

What is a chemical change?

Back

A chemical change is a change that results in the formation of new chemical substances. It involves a chemical reaction and the rearrangement of atoms. Examples include burning, rusting, and cooking.

Front

What evidence indicates a chemical change has occurred?

Back

Evidence of a chemical change includes color change, temperature change, gas production, and the formation of a precipitate.

Front

What happens to molecules during a physical change?

Back

During a physical change, the arrangement of molecules may change, but their chemical structure remains the same.

Front

What happens to molecules during a chemical change?

Back

During a chemical change, the bonds between atoms are broken and new bonds are formed, resulting in the creation of new substances.

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What is an example of a physical change?

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An example of a physical change is ice melting into water.

Front

What is an example of a chemical change?

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An example of a chemical change is baking a cake, where ingredients react to form a new substance.

Front

How does heat affect physical changes?

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Heat can cause physical changes by providing energy that allows substances to change state, such as melting or boiling.

Front

How does heat affect chemical changes?

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Heat can provide the energy needed for a chemical reaction to occur, often resulting in the formation of new substances.

Front

What is the difference between a reversible and irreversible change?

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A reversible change can be undone (e.g., melting ice), while an irreversible change cannot be undone (e.g., cooking an egg).