Question

A cylinder of 1 L volume is to be filled with at ${27}^{o}C$ and $82atm$ pressure.What will be the volume and density of $H_2$ at STP?

• A. 86.2 L
• B. 74.62 L
• C. 92.2 L
• D. 52.4 L

Answer 1

Answer: (B)

74.62 L

Given:-

$P_1=82atm$

$V_1=1L$

$T_1=27℃=(27+273)K=300K$

At STP,

$P_2=1atm$

$V_2=V=?$

$T_2=273.15K$

From ideal gas equation,

$\frac{P_1{V}_1}{T_1}=\frac{P_2{V}_2}{T_2}$

$\Rightarrow \frac{82\times 1}{300}=\frac{1\times V}{273.15}$

$\Rightarrow V=74.661\approx 74.62L$

As we know that,

$Density=\frac{mass}{volume}$

Molecular mass of $H_2=2g$

$\therefore Density=\frac{2}{74.62}=0.0268kg/m^3\approx 0.027kg/m^3(\because 1g/L=1Kg/m^3)$

Hence, volume and density of $H_2$ at STP is $74.62L$ and $0.027Kg/m^3$ respectively.