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Taylormartinez
Oct 12, 2009, 03:19 PM
During exercise you lost 2.0 points of water from sweating. IF all the water is evaporated, how much entery did the ater absorb from your body? Answer in kj

Perito
Oct 13, 2009, 03:19 PM
During exercise you lost 2.0 pounds of water from sweating.
If all the water evaporated, how much energy did the water absorb from your body?


1. Look up the latent heat of vaporization of water -- also called the enthalpy of vaporization.

Enthalpy of vaporization - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Enthalpy_of_vaporization)

2. The enthalpy of vaporization may be given in cal/g or kJ/kg or kJ/mol or any of a number of other units. You'll have to convert the 2 pounds of water to whatever the units are (kg, g, mol). If you multiply by the enthalpy of vaporization, you'll get a value of energy in units of cal, kJ, or simply J

3. Convert the value of energy to the units you need to work with.