Ratio of specific heats $$\gamma$$ of a mixture of gases is given by $$\gamma = 1 + \frac{R(n_1 + n_2)}{n_1C_{v1} + n_2C_{v2}}$$ where $$C_{v1}$$ and $$C_{v2}$$ are the specific heats at constant volume of the two gases in the mixture and $$\gamma$$ is the ratio of specific heats, $$n_1$$ and $$n_2$$ are the number of moles of the gas in the given mixture.<br>Find the velocity of sound in a mixture by equal volumes Hydrogen and Helium at $$27^\circ\text{C}$$. Specific heats at constant volume for Hydrogen and Helium are $$\frac{5R}{2}$$ and $$\frac{3R}{2}$$ respectively.