Mass \(=28 \,g\)

\(P_i=10 \,atm \quad T_i=57^{\circ} C =330 \,K\)

\(P_f=5 \,atm \quad T_f=27^{\circ} C =300 \,K\)

Volume is kept constant.

\(P_i=K \times n_i T_i \quad \dots (i)\)

\(P_f=K \times n_f T_f \quad \dots (ii)\)

Dividing \((i)\) by \((ii)\)

\(\frac{P_i}{P_f}=\frac{n_i}{n_f} \frac{T_i}{T_f}\)

\(\frac{n_i}{n_f}=\frac{10}{5} \times \frac{300}{330}\)

or \(\frac{n_i}{n_f}=2 \times \frac{10}{11}\)

\(\frac{n_i}{n_f}=\frac{20}{11}\)

Now \(n_i=1\) mole of \(N _2\) \(n_f=\frac{11}{20}\) moles

or Mass of \(N _2\) left \(=\frac{11}{20} \times 28\)

\(\therefore \text { Quantity released }=28-\frac{11}{20} \times 28\)

\(=\frac{9}{20} \times 28=\frac{63}{5} g\)