why is it when vacuum chamber is vacuumed, sponge soaked with water frozed?

Question

I have a vacuum oven. heat . hold. stop heater. vacuum on. hold. stop vacuum. this goes on for many cycles.
water boils at 100deg C at 760 Torr.
water boiling point decreases as pressure drops ( vacuum ).
wetted part - shouldn't it dried under lower pressure.
Anything to do with sudden vacuum, temp drops?
Not very clear on this theory. Please explain. Thanks.

Answer 1

Whatever temperature the water in the sponge was, that's a measure of the energy of the individual molecules. Actually it's the energy of an average molecule. As with most things you average, some individuals had more than the average, some less.

When you pull a vacuum, the molecules with the most energy go free because the pressure is less than the vapor pressure. This continues and after a while only the molecules with the least energy remain. And they had so little that they form ice.

Answer 2

Not sure if that was in English....but...PV = nRT......Ideal Gas Law.

Pressure and Temperature are proportional.

Lower pressure.....Temperature also lowers.