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 tearing.

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

What happens to the weight of matter during a physical change?

Back

The weight of matter stays the same during a physical change.

Front

What happens to the weight of matter during a chemical change?

Back

The weight of matter stays the same during a chemical change, according to the Law of Conservation of Mass.

Front

What is the Law of Conservation of Mass?

Back

The Law of Conservation of Mass states that matter cannot be created or destroyed in a chemical reaction; the total mass of the reactants equals the total mass of the products.

Front

Give an example of a physical change.

Back

An example of a physical change is ice melting into water.

Front

Give an example of a chemical change.

Back

An example of a chemical change is iron rusting.

Front

What happens to cake batter when it is baked?

Back

When cake batter is baked, it undergoes a chemical change, resulting in a new substance: cake.

Front

What is an indicator of a chemical change?

Back

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

Front

Is tearing paper a physical or chemical change?

Back

Tearing paper is a physical change because the paper's chemical composition remains the same.