Chemical vs 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 breaking, melting, or dissolving.

Front

What is a chemical change?

Back

A chemical change is a change that results in the formation of one or more new substances with different properties. Examples include rusting, burning, and cooking.

Front

When you break a cracker into pieces, what type of change is it?

Back

Physical change.

Front

What happens to the substances in a chemical change?

Back

In a chemical change, one or more new substances are created.

Front

What is a mixture?

Back

A mixture is a combination of two or more substances where each retains its own properties and can be separated by physical means.

Front

Why is a mixture considered a result of a physical change?

Back

Because the parts of a mixture can be separated without changing their chemical identities.

Front

Is sharpening a pencil a physical or chemical change?

Back

Physical change.

Front

What is a sign that a chemical reaction has occurred?

Back

Formation of a gas.

Front

What are some common signs of a chemical change?

Back

Common signs include color change, temperature change, gas formation, and the formation of a precipitate.

Front

Can physical changes be reversed?

Back

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