Question

The nitrogen gas pressure inside a container of volume $2.6 \, cm ^{3}$ is $2.3$ atm at $27^{\circ} C$. The approximate number of moles of nitrogen present in the container is $\left[R=0.0821 L\right.\, atm \left.mol ^{-1} K ^{-1}\right]$

• A. $4 \times 10^{-3}$
• B. $1.7 \times 10^{-4}$
• C. $4 \times 10^{-4}$
• D. $2 \times 10^{-4}$

Answer 1

Answer: (D)

Given,

Pressure of $N _{2}$ gas $=2.3$ atm

Volume $=2.6 \,cm ^{3} $

$=2.6 \times 10^{-3} \,L$

Temperature $=27^{\circ} C +273 $

$=300\, K$

Gas constant $(R)=0.0821 \,L$ atm $mol ^{-1} \,K ^{-1}$

From, ideal gas equation

$p V=n R T$

$n=\frac{p V}{R T}$

$n =\frac{2.3 atm \times 2.6 \times 10^{-3} L }{0.0821\, \,L\, atm\, mol ^{-1} / K \times 300 K } $

$n =2 \times 10^{-4} \, mol$