Question $3$

For ethane, $Pc=48\mathrm{.}2$atm and $Tc=305\mathrm{.}4K.$ Calculate the pressure exerted by $74\mathrm{.}8g$ of $C_2{H}_6$ in a $200-c{m}^3$ vessel at $37\mathrm{.}5C$ using $($a$)$ the ideal$-$gas law; $($b$)$ the van der Waals equation.