Question

The density of $O_2$ is 16 kg/m${}^3$ at NTP .At what temperature its density will be 14 kg/m${}^3$ ? consider that the pressure remains constant.

• A. ${39}^{o}C$
• B. ${43}^{o}C$
• C. ${57}^{o}C$
• D. None of these

Answer 1

The correct option is A ${39}^{o}C$

We know that, $PV=nRT$

or, $P=\frac{m}{VM}RT=\frac{\rho }{M}RT$

At $NTP$, $T=273K$

$P$ is constant

Therefore, ${\rho }_1{T}_1={\rho }_2{T}_2$

$\Rightarrow 16\times 273=14\times T_2$

$\Rightarrow T_2=312K$ or ${39}^{0}C$

$\therefore$ Correct answer will be A.