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  4. For an ideal monoatomic gas, the universal gas constant R is n times the molar heat capacity at constant pressure Cp. Here n is :

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 :

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Solution:

Given that $R=n C_{p}$
$R=\frac{n \gamma R}{\gamma-1}$
$n=\frac{\gamma-1}{\gamma}$
For a monoatomic gas, $\gamma=1.66$
$n=\frac{1.66-1}{1.66}=0.39 \approx 0.4$

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