The density of oxygen is $1.43g{L}^{-1}$ at STP. The density of oxygen at ${17}^{\circ }\text{C}$ and $800torr$ is:

The correct option is A $1.417{\text{g L}}^{-1}$
At STP,
$P_1=760torr;T_1=273K;d_1=1.43g{L}^{-1}$
At given conditions,
$P_2=800torr;T_2=290K;d_2=?]$

We know, $PM=dRT$
$\therefore \frac{d_2}{d_1}=\frac{P_2}{T_2}\times \frac{T_1}{P_1}$

$d_2=\frac{P_2}{P_1}\times \frac{T_1}{T_2}\times d_1$

$=\frac{800}{760}\times \frac{273}{290}\times 1.43$

$=1.417{\text{g L}}^{-1}$