Question

The real gas equation at high pressure will be:

• A. $PV+Pb=RT$
• B. $PV-Pb=RT$
• C. $PV-Pb=-RT$
• D. $PV+Pb=-RT$

Answer 1

The correct option is B $PV-Pb=RT$

According to van der Waals' equation of state,
$(P+\frac{a}{V^2})(V-b)=RT$ (for one mole of gas)
For high pressure, we can neglect the term $\frac{a}{V^2}$
$\therefore P(V-b)=RT$
$⟹PV-Pb=RT$