$3.$ A $30-$m$3$

tank contains $14$ m$3$

of liquid n$-$butane in equilibrium with its vapor at $25\backslash$deg C$.$

Estimate the mass of n$-$butane in the tank. The vapor pressure of n$-$butane at the given

temperature is $2\mathrm{.}43$ bar. Use Pitzer$$s and Rackett$$s equations when applicable.

$1)$ Calculate the mass of n$-$butane vapour: mvap$=98$ kg

$2)$ Calculate the mass of n$-$butane liquid: mliq $=7983$ kg

$3)$ The total mass of n$-$butane in the tank: m $=8081$ kg Just $2$ and $3$ please