What Limits Boiling Rate?

Most recent answer: 01/04/2013

Q:
Boiling 10liters of water for 1hr.resulted in 2 liters evaporation that is 20 percent,now if I was to boil 20 liters using the same pot and heat setting will I lose 2 liters or 4 liters and why.thank you very much for help.Emil.
- Emil (age 34)
Montreal qc. Canada
A:
It should be about the same amount, not the same percent. In a simple model, the heat goes in to first heat the water to 100°C, then all subsequent heat goes into the latent heat of boiling. With the 20L of water, more heat is needed at the start to get the water to boiling. That leaves a little less for supplying latent heat, and thus could give a little less boiling than with the 10L. However, there are other complications involving the rate at which heat is just lost to the outside that make the calculation a little more complicated.

Still, as a first estimate I'd say assume that slightly less than 2L will boil away from the 20L.


Mike W.

(published on 01/04/2013)