Q: If one mole of a monoatomic gas is mixed with one mole of a diatomic gas, the value of γ for the mixture is

(a) 1.40

(b) 1. 50

(c) 1.53

(d) 3.07

Ans: (b)

Sol: Here , n_{1} = 1 , γ_{1} = 5/3

n_{2} = 1 , γ_{1} = 7/5

Since , $\large \frac{n_1 + n_2}{\gamma -1} = \frac{n_1}{\gamma_1 -1} + \frac{n_2}{\gamma_2 -1}$

$\large \frac{1 + 1}{\gamma -1} = \frac{1}{5/3 -1} + \frac{1}{7/5 -1}$

On solving , γ = 1.5