Physical vs Chemical Changes

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 changes in state (like melting or freezing) and changes in appearance (like cutting or 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 the breaking and forming of bonds between atoms. Examples include rusting, burning, and cooking.

Front

What happens to the atoms during a chemical change?

Back

During a chemical change, atoms rearrange and link up in different ways to form new substances.

Front

What is an example of a physical change that results in a color change?

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An example is when a red candy dissolves in water, turning the water pink.

Front

What is an example of a chemical change?

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An example of a chemical change is when iron rusts, forming iron oxide.

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

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A physical change does not alter the chemical composition of a substance, while a chemical change results in the formation of new substances.

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What is an indicator of a chemical change?

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Indicators of a chemical change include color change, gas production, temperature change, and the formation of a precipitate.

Front

What is an example of a physical change that does not involve a change in chemical composition?

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An example is ice melting into water; the chemical composition of H2O remains the same.

Front

What is the role of thermal energy in physical and chemical changes?

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Thermal energy can cause physical changes by changing the state of matter (like melting) and can also provide the energy needed for chemical changes to occur.

Front

What is a precipitate?

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A precipitate is a solid that forms and settles out of a liquid mixture during a chemical reaction.