Question

Assertion : At high pressure, the compression factor $Z$ is $\left(1+\frac{P b}{R T}\right)$.
Reason : At high pressure van der Waals' equation is modified as $P(V-b)=R T$.

• A. If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
• B. If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
• C. If Assertion is true but Reason is false.
• D. If both Assertion and Reason are false.

Answer 1

Answer: (A)

van der Waals' equation is
$\left(P+\frac{a}{V^{2}}\right)(V-b)=R T$
at high pressure
$P(V-b)=R T$
$P V-P b=R T$
$\frac{P V}{R T}=\left(1+\frac{P b}{R T}\right)$
if $\frac{P V}{R T}=Z,$ then
$Z=\left(1+\frac{P b}{R T}\right)$