Question

What happens when a refrigerant evaporates?

A. It compresses itself and doesn't contact its surroundings.
B. It expands rapidly and absorbs heat from its surroundings.
C. The pressure on it increases, and it radiates heat to its surroundings.
D. The surface tension on it increases, and it sticks to its surroundings.

Answer 1

B. It expands rapidly and absorbs heat from its surroundings.

Step-by-step explanation:

When a refrigerant evaporates, it changes from a liquid to a gas or vapor. During this phase change, the refrigerant absorbs heat from its surroundings, which causes it to expand rapidly. This is the basis for how refrigeration and air conditioning systems work. The refrigerant is evaporated in an evaporator coil, and as it absorbs heat from the surrounding air or water, it cools the air or water down.

Option A is incorrect because when a refrigerant evaporates, it does not compress itself. Instead, it expands.

Option C is incorrect because when a refrigerant evaporates, the pressure on it decreases rather than increases, as it changes from a liquid to a gas or vapor.

Option D is incorrect because the surface tension of a refrigerant does not increase when it evaporates, nor does it stick to its surroundings.

Answer 2

B. It expands rapidly and absorbs heat from its surroundings.

When a refrigerant evaporates, it changes from a liquid state to a gaseous state. During this process, the refrigerant absorbs heat from its surroundings, causing the temperature of the surroundings to decrease. This is the basic principle behind how refrigeration systems work. The refrigerant is evaporated in the evaporator coils of the system, and the resulting cool air is circulated to cool the space or item being refrigerated. Additionally, the evaporated refrigerant expands rapidly, which is why it is often used in compression-based cooling systems, where it is compressed to increase its pressure, and then allowed to expand rapidly, further cooling the surroundings.