What is a physical change?

• A change in traits, such as color, size, or shape, that does not change what the substance is made of.

• A change that creates a new substance.

• A change that only happens with liquids.

• A change that always involves heat.

Which of the following is an example of a physical change?

• A melted juice pop

• Burning wood

• Rusting iron

• Baking a cake

What happens to an inflated balloon when you put it in the freezer?

• It shrinks because the volume of air changes.

• It pops immediately.

• It changes color.

• It turns into a liquid.

Why does the balloon return to its original size after being taken out of the freezer?

• The air inside warms up and expands.

• The balloon is made of a special material.

• The freezer repairs the balloon.

• The balloon absorbs water.

How does the picture of the balloon help you understand the connection between temperature and the volume of a gas?

• It shows that when the temperature decreases, the volume of the balloon decreases, and when the temperature increases, the volume returns to normal.

• It shows that balloons always stay the same size.

• It shows that balloons change color in the cold.

• It shows that balloons are only used for decoration.

What is the process called when a liquid becomes a solid due to a decrease in temperature?

• Melting

• Freezing

• Evaporation

• Condensation

What happens to the particles of a liquid as it gets colder?

• They move faster

• They disappear

• They slow down

• They change color

Which process describes particles leaving a liquid and becoming a gas?

• Freezing

• Melting

• Evaporation

• Condensation

Explain why puddles of water disappear after it rains, using your understanding of evaporation.

• The water is absorbed by the ground only

• The water turns into ice

• The water particles leave the liquid and become gas, rising into the air

• The water is eaten by animals

If you wanted to turn a solid into a liquid, what would you need to do to its particles?

• Cool them down

• Remove all energy

• Heat them up so they gain energy and move past each other

• Freeze them