Chemical changes

Front

What is a physical change?

Back

A change in the size, shape, or state of matter without forming new substances.

Front

What is a chemical change?

Back

A change in which new substances are formed.

Front

What happens during a chemical change?

Back

New substances are created, often with different properties than the original substances.

Front

What is an example of a physical change?

Back

Melting ice or breaking a glass.

Front

What is an example of a chemical change?

Back

Burning wood or rusting iron.

Front

What indicates a chemical change has occurred?

Back

Signs include color change, temperature change, gas production (bubbles), and formation of a precipitate.

Front

Can a physical change be reversed?

Back

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

Front

Can a chemical change be reversed?

Back

Chemical changes are usually not reversible by simple physical means.

Front

What is the law of conservation of mass?

Back

In a chemical reaction, matter is neither created nor destroyed; it is conserved.

Front

What is a reactant?

Back

A substance that undergoes a chemical change in a reaction.