Latent Heat of Vaporization Equation

[anubis512]

Hi All,

I'm trying to calculate the latent heat of vaporization of a chemical using the equation found in Perry's Chemical Handbook, Table 2-150. It gives the latent heat equation and chemical specific constants. My issue is I can't get that equation, which outputs J/kmol, to convert correctly to BTU/lb. I tried using water as a test chemical to make sure I was using the equation correctly, and it won't work.

The table says the listed are "latent heat values at Tmin X 1E-07". For water, this comes out to (and is listed as)4.4733x10^-7 J/kmol at 0C.


Does anyone have experience with using this equation from Perry's or converting it to BTU/lb?



Thanks!

 

[25362]

The tabulated value for water should be multiplied by 10[sup]7[/sup] since it has been given as multiplied by 10[sup]-7[/sup]. Therefore, the reading should be 4.4733[×]10[sup]7[/sup] J/kmol.

To get J/g = kJ/kg, divide this value by 18,015 g/kmol.
The conversion from kJ/kg to Btu/lb is an easy operation.

 

[25362]

You may use:

1 Btu/lb = 2.326 kJ/kg​