Question

At relatively high pressure, van der Waal's equation reduces to

• A. PV = RT
• B. PV = RT - a/V
• C. PV = RT + Pb
• D. PV = RT -$a/V^2$

Answer 1

Answer: (C)

PV = RT + Pb

Answer 2

At high pressure, the pressure correction for 1 mole of gas is negligible $\therefore \, \frac{a}{V^2}$ = 0 . However the volume correction cannot be neglected . $\therefore$ van der Waals equation reduces to (P + 0) (V -b) = RT...... for 1 mole. or PV = RT + Pb.