Chemical Changes Quiz

Which change is easier to reverse?

• Physical changes

• Chemical changes

When do chemical changes take place? What happens?

• Chemical changes occur when substances interact to form new substances

• Chemical changes do not occur naturally.

• Chemical changes happen without any energy exchange.

• Chemical changes only occur in laboratory settings.

What is needed for some chemical changes to begin?

• Energy

• No energy required

What can produce energy when substances are combined in chemical changes?

• Fire

• Glow stick

• Both

The total amount of matter is always the same before and after a chemical change

• True

• False

Sugar dissolves in water

• Chemical Change
• Physical Change

Salt dissolves in water

• Chemical Change
• Physical Change

A physical change _____________ the identity of the substance.

• changes

• maintains

Is copper tarnishing a physical or chemical change?

• Physical

• Chemical

Photosynthesis is the process in which plants use sunlight to convert water and carbon dioxide into glucose and oxygen. Which of the following statements explains why photosynthesis is a chemical change?

• New substances are formed with properties that are different from the original substances.

• New substances are formed but their properties are the same as the original substances.

• No new substance is formed but some of the properties change.

• No new substance is formed and the change is easily reversible.

Answer explanation

New substances are formed with properties that are different from the original substances.