Physical vs. 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 changes in state (like melting or freezing) and changes in shape or size.

Front

What is a chemical change?

Back

A chemical change is a change that results in the formation of new chemical substances. It involves a chemical reaction and changes the chemical composition of the substance. Examples include burning, rusting, and baking.

Front

Give an example of a physical change.

Back

Mowing the grass is an example of a physical change because it changes the height of the grass but does not change its chemical composition.

Front

Give an example of a chemical change.

Back

Baking bread is an example of a chemical change because it involves a chemical reaction that transforms the ingredients into a new substance.

Front

What happens to chemical energy when you eat food?

Back

When you eat food, you turn chemical energy into thermal energy as your body metabolizes the food.

Front

What is an example of a physical change involving water?

Back

Freezing water is an example of a physical change because it changes the state of water from liquid to solid without changing its chemical composition.

Front

What is an example of a chemical change involving plants?

Back

A plant collecting sunlight and turning it into food through photosynthesis is an example of a chemical change.

Front

What is the difference between physical and chemical changes?

Back

Physical changes do not alter the chemical composition of a substance, while chemical changes do result in the formation of new substances.

Front

What happens when a glass cup falls and shatters?

Back

When a glass cup falls and shatters, it is an example of a physical change because the glass is broken into pieces but remains glass.

Front

What is an example of a chemical change in cooking?

Back

Baking a cake is an example of a chemical change because the ingredients undergo a chemical reaction to form a new product.