Question

Density of a gas is found to be $5.46 g/dm^3$ at $27 \,^{\circ}C$ and $2$ bar pressure. What will be its density at $STP$?

• A. $3.0\, g$ $dm^{-3}$
• B. $5.0\, g$ $dm^{-3}$
• C. $4.0\, g$ $dm^{-3}$
• D. $10.82\, g$ $dm^{-3}$

Answer 1

Answer: (A)

$3.0\, g$ $dm^{-3}$

Answer 2

$d=\frac{PM}{RT}$ $\quad$ or $\quad$ $d$ $\propto$ $\frac{P}{T}$ $\frac{d_{1}}{d_{2}}$ =$\frac{P_{1}}{P_{2}}$ $\times\frac{T_{2}}{T_{1}}$ $\quad$ or $\quad$ $d_{2}$ =$\frac{d_{1}\times P_{2}\times T_{1}}{P_{1}\times T_{2}}$ $d_{2}$ =$\frac{5.46\times1\times300}{2\times273}$ = $3.0 \,g$ $dm^{-3}$