Question

part c: multiple choice (23–30)
circle the best answer.

1. which process adds water vapor to the air?

a. condensation
b. evaporation
c. freezing
d. melting

1. what happens to air when it warms up?

a. it becomes heavier and sinks
b. it turns into liquid
c. it rises because it is less dense
d. it becomes a cloud immediately

1. which word best explains the overall condition of the atmosphere?

a. temperature
b. energy
c. weather
d. stability

Explanation:

Question 23

To solve this, we analyze each option:

• Option A (Condensation): This is the process where water vapor turns into liquid water (removes vapor from air).
• Option B (Evaporation): This is when liquid water turns into water vapor, adding vapor to the air.
• Option C (Freezing): Involves liquid turning to solid (not related to water vapor in air).
• Option D (Melting): Solid turning to liquid (also not related to water vapor).

So evaporation adds water vapor to the air.

Analyze the behavior of air with temperature:

• When air warms, its density decreases (since warmer air molecules move more and spread out). Less dense air rises (as denser air sinks).
• Option A: Warmer air is less dense, so it does not become heavier and sink.
• Option B: Air turning to liquid is condensation (requires cooling, not warming).
• Option C: Correct, as warm air is less dense than cooler air, so it rises.
• Option D: Cloud formation (condensation) needs cooling, not immediate warming.

Define each term:

• Option A (Temperature): Measures heat intensity (not overall atmospheric condition).
• Option B (Energy): A general term (not specific to atmospheric condition).
• Option C (Weather): Defined as the overall condition of the atmosphere (temperature, humidity, precipitation, etc.) at a time/place.
• Option D (Stability): Refers to air’s tendency to rise/sink (not the overall condition).

Answer:

B. Evaporation

Question 24