Which best compares freezing and condensation? a. both involve changes between liquids and gases. b. both involve changes between gases and solids. c. both involve the release of heat. d. both involve the absorption of heat.

c. Both involve the release of heat.

Explanation:

- Freezing occurs when a liquid turns into a solid: during this process, heat is released from the substance to the environment (because the molecules in the liquid initially move faster, then after the process the molecules do not move anymore, since in a solid they are bond together)

- Condensation occurs when a gas turns into a liquid: during this process, heat is released from the substance to the environment (because the molecules in the gas initially move faster, then after the process the molecules move slower, as in a liquid they are more attracted to each other)

Given these definitions, we can now analyze each option:

a. Both involve changes between liquids and gases.   --> false. In fact, freezing does not involve gases.

b. Both involve changes between gases and solids.   --> false. In fact, condensation does not involve solids.

c. Both involve the release of heat.   --> true: both processes involve the release of heat.

d. Both involve the absorption of heat. --> false: none of the two processes involve the absorption of heat, as they both release heat, instead.

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.

powerful computers now, not then