Question

A sample of `H_2O` with a mass of 46.0 grams has a temperature of 100°C. How many joules of energy are necessary to boil the water?

Answer 1

If you said `Delta=2.09*J*g^-1xx46.0*g` you would be wrong.

Explanation:

The heat of vaporization of water, `DeltaH_("vap")~=2.26*kJ*g^-1`. Your heat of vaporization is out by three order of magnitude, This is all too easy to do of course.