## What factors determine the rate of evaporation?

And if I'm heating a liquid that contains things that evaporate at different temperatures, will I have an increasing amount of trouble separating these things as I increase the amount of heat applied?
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 If I mix an equal volume of three materials, A, B and C. Each having a different evaporation temperature. Let's say the evaporation temperature of B is equally above the evaporation temp of A as it is below the evaporation temp of C. Would the evaporation temperature of the whole now be equal to the evaporation temperature of material B? Or would material A, having the lowest evaporation temperature, begin to leave the mixture as soon as it's individual evaporation temperature is reached? In other words would there be any advantage to maintaining the mixture at the evaporation temperature of material A? And to explore my original intention a little more let's compare two cylindrical vessels used to evaporate liquids. One twice the diameter of the other, but each holding the same amount of an identical liquid. We'll say the goal is to reduce the volume of liquid by half. Assuming I can apply heat perfectly without losses, would the power requirements to reach the goal be the same? And more importantly, would the evaporation rate be the same? Do I save time with the larger diameter vessel? If so, is it achieved at the cost of an increased amount of power? Is there a simple mathematical relationship in this?

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