Work done by product gas in reversible adiabatic expansion

[Egbert]

I am having trouble calculating the work done by a product gas in reversible adiabatic expansion, and in calculating the final temperature. pV gamma = constant, Cv = constant (assume), gamma = cv + nR / Cv.
anyone who can help me out?

 

[siddharth23]

Work done = ∫P.dV
PV^γ = P₁V₁^γ = P₂V₂^γ

Try substituting one equation in the other and integrating from V₁ to V₂

 

[Egbert]

I only know the V1, V2 and n. Should this work or should I assume a P1 of 1 bar?

 

[Chestermiller]

What parameters do you know about the gas in its initial state before the expansion?

Chet

 

[Egbert]

I

What parameters do you know about the gas in its initial state before the expansion?

Chet

t is a combustion reaction of ethanol, volume is increasing from 0.02 m3 to 0.04 m3 with a starting temperature of 4000 K. Also the amounts are known. (12g ethane and enough oxygen)
Thanks

 

[Chestermiller]

I

t is a combustion reaction of ethanol, volume is increasing from 0.02 m3 to 0.04 m3 with a starting temperature of 4000 K. Also the amounts are known. (12g ethane and enough oxygen)
Thanks

You know the initial volume, the initial number of moles of gas, and the initial temperature. From the ideal gas law, what do you get for the initial pressure?

Chet

 

[siddharth23]

Using PV = nRT and PV^γ = constant, can you devise an equation with 'V' and 'T'?