Answer
$d=9.434\frac{g}{L}$
Work Step by Step
We know that
$PV=nRT$
But $n=\frac{m}{M}$ Where $m$ and$M$ are mass in grams and molar mass respectively
$\implies PV=\frac{mRT}{M}$
This can be rearranged as
$PM=\frac{m}{V}RT$
But $d=\frac{m}{V}$ where $d$ represents density
$\implies PM=dRT$
This can be rearranged as
$d=\frac{PM}{RT}$.....eq(1)
$P=1655psi\times \frac{1atm}{14.7psi}=112.585atm$
$T=20.0+273.15=293.15K$
We plug in the known values in eq(1) to obtain:
$d=\frac{112.585\times 2.0158}{0.08206\times 293.15}=9.434\frac{g}{L}$
