Question

The third virial coefficient of the gas is $4\times {10}^2$ $\left(L/mol\right)$${}^2$ then what will be the volume of 2 moles $He$ gas at $STP$?

[Given: repulsion among gaseous molecules strongly dominates]

• A. 45 litre
• B. 45.4 litre
• C. 45.8 litre
• D. 44.8 litre

Answer 1

The correct option is B 45.4 litre

Since, the repulsion among gaseous molecules strongly predominates. the van der waals coefficient ${}^{\prime }{a}^{\prime }$ can be neglected.
The third viral coefficient $C=b^2=4\times {10}^{-2}(litre/mole{)}^2$
$b=0.2litre/mole$
$P(V-nb)=nRT$
$1atm\times (V-2\times 0.2)=2\times 0.08206Latm/mol/K\times 273K$
$V=45.4L$