To answer the topic title, it's what Overload said: water has a high enthalpy of vaporization. In other words, the surface of the bulb is hot, right? For liquid water to be vaporized into water vapor, it requires a certain amount of energy. Compared to other liquids, water requires a pretty large amount of energy to evaporate. Remember that it's an endothermic process; liquid water takes energy away from the environment to become a gas (water vapor). Energy translates into heat. Heat translates to temperature. Water takes away heat from the bulb surface when it vaporizes, lowering the temperature of the bulb.
Compare this to other liquids, such as ethanol, or acetone, which have much lower enthalpies of vaporization. They take away much less heat than water. So if you were to wet a bulb with 10 mL of water, and then another bulb with 10 mL of ethanol and then compared the temperatures after all the liquid had evaporated from both, the one that was in water would be at a lower temperature (since the water takes more heat away from the bulb than ethanol).
Hmm, I'm not too sure.
Oh, and how does diffusion help cycle minerals and oxygen in deep lakes? This is a weird question I think...
I answered this in the other thread.
You know, maybe I'll make a thread for this kind of thing, so that people don't have to make new ones every time...
