Latent Heat and Steam Formation - Continued.

Phase 1 (from A to B)

In this phase, the temperature of water is raised from 70 deg F to 212 deg F. The temperature rise is 142 deg F (212 –70 = 142).

How much heat did we add? We can figure that out by using the following formula:

Sensible Heat Addition = (Specific Heat) x (Mass) x (Temperature Increase)

In our case we know the following:

Mass = 1 lb

Specific heat of Water = 1

Temperature Increase = 142

Therefore when we plug these numbers in the formula we get:

Sensible Heat Addition = 1 x 1 x 142 = 142 BTU

In this phase, we increase the water temperature to the saturation temperature. We did not add any extra latent heat.