Various vapor pressure & condenser question

#1

Hey!

This seems basic, and it’s probably just the weed clouding my thought process but here goes.

Science fundamentals question here. But I’ve been noticing the differences with vapor pressure/volatility of chemicals and the energy to evaporate (I.e heptane boils higher than ethanol but needs less energy to Evaporate).

I’m curious how this relates to condensing the gas. If I had a 5kw chiller, would it condense the same amount of fluid? Is there a direct relationship between the condensing and evaporating energies required? Do you condense more of a high volatility gas in the same condenser?

Also, if you had a certain size of condenser are you more or less likely to over-run it as a function of vapor pressure?

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#2

energy required for phase change is the same in both directions.

it takes more energy to evap (or condense) a liter of water than a liter of ethanol. same for ethanol vs heptane.

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#3

Do you think that it might take a bit more energy to evaporate an ethanol solution than it takes to condense it based on the different inter-molecular forces being different with the presence of cannabinoids and other components? I dont imagine the difference would be very large, just a thought.

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#4

possibly.
however, from what I’ve seen, most folks oversize their condenser slightly when compared to their evaporator.

I imagine that is because;

if at first it doesn’t evaporate, (you can) try try again.
if it doesn’t condense, you’ve lost it to atmosphere…

as a biologist I guess and iterate.
just like the intelligent designer seems to.

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