Chemical and Physical 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 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 changes the molecular structure of the substance.

Front

What happens to ice when it melts in coffee?

Back

The ice melting is a physical change because the water may be frozen again.

Front

What is a physical property?

Back

A physical property is a characteristic of a substance that can be observed or measured without changing the substance's chemical identity. Examples include color, taste, and boiling point.

Front

What is a chemical property?

Back

A chemical property is a characteristic of a substance that becomes evident during a chemical reaction. Examples include flammability and reactivity.

Front

What is flammability?

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Flammability is a chemical property that describes how easily a substance can catch fire and burn.

Front

What is an example of a physical change?

Back

Inflating a tire with air is an example of a physical change.

Front

What happens to water when it is heated to steam?

Back

When water is heated and changes to steam, it is a physical change because the water can be condensed back into liquid.

Front

Can a physical change be reversed?

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Yes, many physical changes can be reversed, such as freezing and melting.

Front

Can a chemical change be reversed?

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Most chemical changes are not easily reversible, as they result in the formation of new substances.