### Specific Heat Capacity vs Cv(Vap) vs Cp(vap)

Posted:

**Sat Feb 11, 2017 9:15 pm**"A pressure cooker containing 100.0 g of liquid water at 25 C is placed on the stove until all water becomes superheated steam at 121 C. Assume no steam escapes the pressure cooker.

a) Find q from 25C to 100C

b) Find q during boiling

c) Find any other heat gained or lot by the water as it goes from 25C to 121C

For Part C, I used q = m C DeltaT.

m = 100.0 g, T = 21C, C = 2.01 J/(Cg), which is the specific heat capacity of water vapor. Why is my value of C wrong? I was supposed to use Cv(vap) but I have never used this before on questions involving fusion/vaporization. I have always used the specific heat capacity of (material) vapor -- water vapor in this case, which was wrong. Can someone please explain?

a) Find q from 25C to 100C

b) Find q during boiling

c) Find any other heat gained or lot by the water as it goes from 25C to 121C

For Part C, I used q = m C DeltaT.

m = 100.0 g, T = 21C, C = 2.01 J/(Cg), which is the specific heat capacity of water vapor. Why is my value of C wrong? I was supposed to use Cv(vap) but I have never used this before on questions involving fusion/vaporization. I have always used the specific heat capacity of (material) vapor -- water vapor in this case, which was wrong. Can someone please explain?