Vanderwaal's constant for a gas `a=3.67 atm "lit"^() "mol"^(-1) b=0.0408 '"lit mol"^(-1)`. Find the critical temperautre and critical pressure of the gas.

Explanation

Given : `a=3.67 atm "lit"^(-2) "mol"^(-1)`
`b=0.0408 "lit mol"^(-1)`
`R=0.821 atm lit K^(-1)"mol"^(-1)`
Sol (i) `T_(C)=(8a)/(27Rb)`
`=(8xx3.67)/(27xx0.82xx0.04080=324.7 K`
`T_(C)=324.7 K`
(ii) `P_(C)=(a)/(27b^(2))`
`=(3.67)/(27xx(0.0408)^(2))=81.6`
`P_(C)=81.6 atm`.