Physical and 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 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. It involves a chemical reaction and includes changes like burning, rusting, and cooking.

Front

What are some signs of a chemical change?

Back

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

Front

Is melting ice a physical or chemical change?

Back

Melting ice is a physical change because it changes from solid to liquid without altering its chemical composition.

Front

What happens to the temperature of water when a chemical change occurs?

Back

In some chemical changes, the temperature of the water may change, indicating that a reaction is taking place.

Front

Can color change indicate a physical change?

Back

Yes, color change can indicate a physical change, but it can also indicate a chemical change depending on the context.

Front

What is an example of a chemical change?

Back

An example of a chemical change is wood burning, which produces ash, smoke, and heat.

Front

What is an example of a physical change?

Back

An example of a physical change is crumpling paper, which alters its shape but not its chemical structure.

Front

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

Back

A physical change does not change the substance's chemical identity, while a chemical change results in new substances being formed.

Front

What does it mean when a substance dissolves in water?

Back

When a substance dissolves in water, it undergoes a physical change, as its chemical identity remains the same.