Specific heat at constant pressure of helium, Cp' = 2.5 R
Specific heat at constant pressure of hydrogen, Cp" = 3.5 R
Specific heat at constant volume of helium, Cv' = 1.5 R
Specific heat at constant volume of hydrogen, Cv" = 2.5 R
n1 = n2 = 1 mol
For the mixture of two gases,
[n1 + n2 ] CvdT = n1C'vdT + n2C"vdT,
where is the heat capacity of the mixture.
Cp = Cv + R = 2R + R = 3R