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. Examples include rusting, burning, and baking.

Front

What happens to the mass when substances are combined?

Back

The total mass of the substances combined is equal to the sum of their individual masses. For example, 100 grams of sand + 200 grams of soil + 200 grams of pebbles = 500 grams of potting soil.

Front

What is rusting?

Back

Rusting is a chemical change that occurs when iron reacts with oxygen and moisture, forming iron oxide (rust). It typically happens in wet conditions.

Front

Is baking a cake a chemical change or a physical change?

Back

Baking a cake is a chemical change because it involves a chemical reaction that transforms the batter into a new substance (cake).

Front

What is an example of a physical change?

Back

An example of a physical change is water freezing into ice. The water changes state but remains H2O.

Front

What is an example of a chemical change?

Back

An example of a chemical change is the process of digestion, where food is broken down into new substances.

Front

What occurs during a chemical change?

Back

During a chemical change, bonds between atoms are broken and new bonds are formed, resulting in new substances.

Front

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

Back

A physical change does not change the chemical composition of a substance, while a chemical change results in the formation of new substances.

Front

What is an example of a substance undergoing a physical change?

Back

An example is ice melting into water; it changes state but remains the same substance.