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Q.
For an ideal monoatomic gas, the universal gas constant $R$ is $n$ times the molar heat capacity at constant pressure $C_{p}$. Here $n$ is :
Thermodynamics
Solution:
Given that $R=n C_{p}$
$R=\frac{n \gamma R}{\gamma-1}$
$n=\frac{\gamma-1}{\gamma}$
For a monoatomic gas, $\gamma=1.66$
$n=\frac{1.66-1}{1.66}=0.39 \approx 0.4$