Diffusion

Zara's mother opens a bottle of perfume. Zara is at the other side of the room. After a few minutes, Zara can smell the perfume.

Which of these explains why Zara smells the perfume?

• All the gas particles of the perfume move in one direction

• All the gas particles of the perfume move randomly.

• All the particles in the air move in one direction.

• All the particles in the air are stationary (not moving).

Diffusion is quicker/faster in ..........................

• solids

• liquids

• gases

An increase in temperature does what to diffusion?

• Speeds it up

• Slows it down

• Stops it all together

• Nothing

The higher the temperature, the higher the rate of diffusion.

• True

• False

A compound, X, has a melting point of 71°C and a boiling point of 375°C. Which statement about X is correct?

• It is a liquid at 52°C and a gas at 175°C

• It is a liquid at 69°C and a gas at 380°C

• It is a liquid at 75°C and a gas at 350°C

• It is a liquid at 80°C and a gas at 400°C