Question

. How much heat would have to be added to the 2000 g of water to completely vaporize it (turn all 2000 g of water at 100 °C to 2000 g of water vapor at 100 °C)? The heat of vaporization of water, DHvap = 40.7 kJ/mol.

Answer 1

Answer:

4520 kJ

Explanation:

To make a substance transition phases an energy must be applied, this is know as the latent heat.

Water has a latent heat of 40.7 KJ/mol to turn into vapor.

The molecule of water has a molecular weight of 18. This means that a mol of water weights 18 grams.

With this we can convert the latent heat to use grams instead of mols

$40.7 \frac{kJ}{mol} * \frac{1 mol}{18 g} = 2.26 \frac{kJ}{g}$

Now, the heat needed to vaporize water is simply:

Q = m * DHvap = 2000 g * 2.26 kJ/g = 4520 kJ