Question

The vander waals constants for $HCl$ are a $371.843KPa$ and$b=40.8c{m}^{3}mo{l}^{-1}$. Choose the correct options:

• A. The critical pressure is $8.273MPa$
• B. The critical temperature is $224.8K$
• C. The critical volume is $122.4c{m}^3$
• D. The critical temperature is $324.8K$

Answer 1

The correct option is A The critical pressure is $8.273MPa$

Critical pressure$P_c=\frac{a}{27b^2}$

given $a=371.843KPa=371.843\times {10}^{-3}$ Pa

$b=40.8{cm}^3{mol}^{-1}$

$P_c=\frac{371.843\times {10}^3}{27\times (40.8{)}^2\times {10}^{-6}}=8.273\times {10}^6$

$P_a$ $=8.273$ MPa