Physical and 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 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. Examples include burning, rusting, and cooking.

Front

Is melting ice a physical or chemical change?

Back

Melting ice is a physical change because the ice changes from solid to liquid but remains water (H2O).

Front

Is burning wood a physical or chemical change?

Back

Burning wood is a chemical change because it transforms the wood into ash, smoke, and gases, creating new substances.

Front

What happens to the molecules during a physical change?

Back

During a physical change, the arrangement of molecules may change, but the molecules themselves remain the same.

Front

What happens to the molecules during a chemical change?

Back

During a chemical change, the bonds between molecules break and new bonds form, resulting in the creation of new substances.

Front

Give an example of a physical change.

Back

An example of a physical change is the freezing of water into ice.

Front

Give an example of a chemical change.

Back

An example of a chemical change is the rusting of iron.

Front

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

Back

The main difference is that a physical change does not create new substances, while a chemical change does.

Front

Can a physical change be reversed?

Back

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