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I know that the Specific Heat Ratio when refering to the gass(es) comming out the back of a rocket engine is the ratio of the specific heats at a constant pressure/volume and then what I am trying to do is use that to help me solve for what the theoretical force I can expect from the rocket using a rather long equation.

Here is my question,

I dont know which specific heat ratios to use and for which gasses?

I have found many tables that list common gasses specific heat rations, the most meaningful being Oxygen gas, Carbon Dioxide, "Air", and Water Vapor/Steam, all of which are involved with a combustion reaction that is taking place inside my solid fueled rocket (propelent is Potassium Chlorate + Sucrose),

the reaction is a combination os two reactions actually,

first the chlorate decomposes: 2KClO3 --> KCl + 3O2

second, the oxygen made during the first reaction is used to combust the sucrose: 12O2 + C12H22O11 + 11H2O

which is then combined to this reaction:

8KClO3 + C12H22O11 --> 12CO2(g) + 11H20(g)

so I know the ratio of gasses to eachother, their molar wieghts, each individuals specific heat ratios, but how do I combine them all to find the overall specific heat ratio of the whole reaction?

is it just the average so to speak of carbon dioxide and water vapor? would I just find out the ratio of carbon dioxide's weight to water vapor's weight and then use that to determine theaveragespecific heat ratio?

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# Specific Heat Ratio - Rocketry

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