Question

An ideal gas exert a pressure of $1.52MPa$ when temperature is $298.15K$ and its volume is ${10}^{-2}{m}^3$. What is the mass density if the gas is oxygen(in $kg/m^3$)?

• A. 20
• B. 30
• C. 45
• D. 50

Answer 1

The correct option is A 20

From the ideal gas equation,

$PV=nRT=\frac{m}{M}RT$

$\rho =\frac{m}{V}=\frac{PM}{RT}$

Thus, $\rho =\frac{(1.52\times {10}^6)(32\times {10}^{-3})}{\left(8.314\right)\left(298.15\right)}\approx 20kg/m^3$

Answer is $20kg/m^3$