Question

If p, V, M, T and R are pressure, volume, molar mass, temperature and gas constant respectively, then for an ideal gas, the density is given by

• A. $\frac{RT}{pM}$
• B. $\frac{p}{RT}$
• C. $\frac{M}{V}$
• D. $\frac{pM}{RT}$

Answer 1

Answer: (D)

$\frac{pM}{RT}$

Answer 2

We know that ideal gas equation is
$\, \, \, \, \, \, \, \, \, \, \, \, \, \, pV = nRT$
$\, \, \, \, \, \, \, \, \, \, \, \, \, \, pV = \frac{w}{M}RT$
$\, \, \, \, \, \, \, \, \, \, \, \, \, \, pM = \frac{w}{V}RT\, \, \, \, \, \, \, \, \, \, \, \, \, \, \, \, \, \Bigg[\because \frac{w}{V}=d\Bigg]$
$\, \, \, \, \, \, \, \, \, \, \, \, \, \, pM = dRT$
$\Rightarrow \, \, \, \, \, \, \, \, d=\frac{pM}{RT}$