Evaporation Amd Condensation

Question 1

Why does the temperature of a liquid decrease after evaporation?

Answer 1

> because the average speed and kinetic energy of the remaining particles decreases.

Question 2

How does evaporation by heating occur?

Answer 2

> the particles absorb heat energy

• they move around more quickly and are able to overcome the forces of attraction
• some escape from the surface

Question 3

What factors affect the rate of evaporation?

Answer 3

> larger surface area
higher temperature
wind

Question 4

Why does wind affect the rate of evaporation?

Answer 4

The particles will be moved away more quickly, maintaining a concentration gradient and increasing the rate of evaporation

Question 5

How does condensation occur?

Answer 5

> The particles lose energy
they move more slowly
they move much closer together and are brought together by forces of attraction

> gas condensed into a liquid

Question 6

What factors affect the rate of condensation?

4

Answer 6

> if temperature of gas is lower

> if temperature of surface it touches of lower

> if the density is higher

> if the airflow is less

Question 7

How does density affect the rate of condensation?

Answer 7

> if the density is higher the particles will be more tightly packed together with stronger forces of attraction.

> fewer particles will be able to overcome this attraction and so instead will form liquids

Question 8

How does airflow affect the rate of condensation?

Answer 8

> if less there will be a higher concentration of water particles and so a higher rate of condensation

Question 9

What is needed for particles to evaporate at temperatures lower than boiling point?

Answer 9

> particles need to be moving in the right direction

> have enough kinetic energy to overcome the forces of attraction