Question

In van der Waals equation at constant temperature $300K$, if $a=1.4atm{L}^{2}mo{l}^{-2}$, $V=100mL$, $n=1mol$, then what is the pressure of the gas?

<!--td {border: 1px solid #cccccc;}br {mso-data-placement:same-cell;}--> AIIMS 2018

• A. $106atm$
• B. $500atm$
• C. $210atm$
• D. $42atm$

Answer 1

The correct option is A $106atm$

At moderate pressure van der Waals equation is given as :
$(P+\frac{a{n}^2}{V^2})\left(V\right)=nRT$
$(P+\frac{1.4}{(0.1{)}^2})\left(0.1\right)=1\times 0.082\times 300$
Solving,
$P=106atm$