Questions: Which factor is important in making it possible to cool yourself by sweating? Think carefully! (a) Molecules collide with varied angles and speeds. (b) Hydrogen bonds are relatively weak. (c) Water has more energy at the body surface. Both (a) and (b). (a), (b), and (c).

Solution Steps

Sweating cools the body through the process of evaporation. When sweat (which is primarily water) evaporates from the skin, it absorbs heat from the body, thus cooling it down.

• (a) Molecules collide with varied angles and speeds: This is a general property of molecules in a liquid state and contributes to the kinetic energy distribution, but it is not directly related to the cooling effect of sweating.
• (b) Hydrogen bonds are relatively weak: This is important because it allows water molecules to break free from the liquid state and evaporate, which is essential for the cooling process.
• (c) Water has more energy at the body surface: This is true because the body heat increases the kinetic energy of water molecules at the surface, facilitating evaporation.

Both (b) and (c) are directly related to the cooling effect of sweating. Weak hydrogen bonds allow water to evaporate, and the increased energy at the body surface aids this process.

Final Answer