Nov. 4, 2019

Degree of Freedom and Specific Heat:

Specific Heat (CP and CV) of a Gas

(1) Specific heat at constant volume(Cv) : 

Cv = (∆T)v/m∆t

Cv = Mcv M(∆Q)v/m∆t = 1(∆Q)v∆T

[As μ=m/M]

(2) Specific heat at constant pressure (Cp) : 

Cp = (∆Q)p/m∆t

Cp = Mcp = M(∆Q)p/m∆T = 1(∆Q)p/μ∆T

As μ=m/M

Mayer’s Formula

Cp = Cv = P∆V/μ∆T = R

This relation is called Mayer’s formula and shows that Cp > Cv, i.e. molar specific heat at constant pressure is greater than that at constant volume.