Substances that take up the shape of their container and have a fixed volume are called

• Solids
• Liquids
• Gases
• Fluids

Which state is best at diffusing

• Gas
• Solid
• Liquid
• Water

Which of these states are fluids (meaning that they can flow)?

• Liquids only
• Liquids and gases
• Gases only
• Solids only

Diffusion occurs when

• a solid expands
• a gas turns into a liquid
• a solid melts
• a gas spreads out to fill its container

The change in state from liquid to gas is known as

• evaporation
• freezing
• melting
• condensation

As the temperature of a substance increases, its particles

• move faster
• move slower
• move further apart, but stay the same speed
• stick together

A substance changes from a liquid into a solid when its particles

• move quicker
• gain energy
• stop moving
• lose energy

When cooled, most substances

• Expand
• Contract and decrease in density
• Contract and increase in density
• Expand and spread out

Sublimation is

• a change from a solid directly into a gas
• a change from a solid into a liquid
• a change from a liquid into a gas
• a process that most things undergo (but not carbon dioxide

A gas turning into a liquid is

• boiling
• transpiration
• evaportation
• condensation