Physical and Chemical Changes in Matter

What happens to a substance during a physical change?

• It always forms a new substance.

• Its physical properties like size or shape change, but it remains the same substance.

• It releases a lot of heat and light.

• Its particles are rearranged to form a completely different material.

When ice melts into water, and then the water evaporates into steam, what type of change is occurring?

• A chemical change, because the state of matter changes.

• A chemical change, because heat is absorbed.

• A physical change, because the substance remains water.

• A physical change, because a new substance is formed.

When you bake cookies, the dough changes color, produces an odor, and gases are released. What type of change is this?

• A physical change, because the ingredients are just mixed.

• A physical change, because the cookies can be unbaked.

• A chemical change, because new substances are formed that cannot be undone.

• A chemical change, because only the shape of the dough changes.

What is the primary outcome of a chemical change?

• The substance changes its shape or size.

• The substance changes its state of matter.

• A new substance with different properties is formed.

• The substance can easily be returned to its original form.

Which of the following is a clue that a chemical change has occurred?

• The substance changes its size.

• The substance changes its state (like from liquid to gas).

• The change can easily be reversed.

• The substance produces light or a new odor.