Chemical vs. 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 changing 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 spoiling.

Front

What happens to a candle when it burns?

Back

When a candle burns, it undergoes a chemical change because it produces new substances, such as carbon dioxide and water.

Front

Is melting ice a physical or chemical change?

Back

Melting ice is a physical change because it changes from solid to liquid but remains water.

Front

What is an example of a chemical change in food?

Back

An example of a chemical change in food is when milk spoils, resulting in a different substance with a different smell and taste.

Front

What happens to gallium when it melts?

Back

When gallium melts, it undergoes a physical change, and a puddle of gallium metal is left behind.

Front

What is an example of a physical change?

Back

An example of a physical change is mixing air into egg whites, which changes their volume but not their chemical structure.

Front

What is carbon dioxide?

Back

Carbon dioxide is a gas produced when something burns, and it can cause candles to go out.

Front

What is the difference between physical and chemical changes?

Back

Physical changes do not create new substances, while chemical changes do.

Front

Can a physical change be reversed?

Back

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