For the molecules of a gas, γ=Cv​Cp​​=1+f2​ , where f is the degree of freedom.Given : γ=1.29 ⇒1+f2​=1.29=79​ ⇒f2​=79​−1 ⇒f2​=72​ ⇒f=7 Therefore, the molecules of this gas have 7 degrees of freedom. But in reality, no gas can have more than 6 degrees of freedom.