From: glhurst@onr.com (Gerald L. Hurst)
Newsgroups: sci.chem
Subject: Re: High-Temperature Equilibrium problem -- need HELP
Date: 6 Nov 1995 23:28:55 GMT
Organization: Consulting Chemist
Lines: 25

In article <47l8d1$rq0@zippy.cais.net>, alchemst@pacificnet.net (John
Milligan) says:

>>  4)  Energy must be conserved.  May I use any reference temperature
>>      I want, or does it have to be close to the eq. temp?  Where
>>      can I find total enthalpy values for these gases at high
>>      temperatures.
>
>Usually the reference values (T = 298.15 K) are used.  These are then 
>assumed to not change much over the temperatures involved.  

The values at high temperature will be quite different from
those at standard temperature. As a first approximation you 
can look use the variable, but known heat capacity values of 
the product gases to estimate the actual enthalpy change at
high temperature. These values are listed to some extent in 
the handbooks. Better yet, try Melvin Cook's book THE SCIENCE
OF HIGH EXPLOSIVES, an ACS monograph published by Reinhold,
1958, 1966. He give a number of the Kp values you seek and
discusses the methods of calculation. You can probably find
later data once you've seen what Cook has to say. I don't
know how accurate his data are but he gives values for about
30 reactions at 1000 to 6000 deg K in a chapter called 
"Calculations of Products of Detonation."

Jerry