KIV: Changes in Matter

What happens to iron when it is heated in the forge?

• It turns into gold.

• It becomes hard and brittle.

• It melts completely.

• It becomes soft and pliable.

What is rust?

• A type of paint.

• A type of metal.

• A chemical change on iron.

• A physical change on iron.

What happens to coal when it burns?

• It becomes a diamond.

• It changes into ash.

• It turns into water.

• It stays the same.

Can materials that have undergone physical changes be easily returned to their original form?

• Only if they are metals.

• Sometimes, it depends on the material.

• No, never.

• Yes, always.

Can materials that have undergone chemical changes be easily turned back into what they started as?

• No, they become new substances.

• Yes, always.

• Only if they are heated.

• Only if they are cooled.