Question

\( 14 g \) of nitrogen occupy \( 0.028 m ^{3} \) at \( 27^{\circ} C \). If the universal gas constant is \( 8.4 J / mol K \). Find the pressure exerted by it. [Molecular weight of nitrogen \( =28] \) [2 Marks] \[ 45 \times 10^{3} N / m ^{2} \]

Answer 1

Mass of gas = 14 g

Molar mass = 28

\(\therefore\) moles n = \(\frac{14}{28} = \frac 12\)

\(V = 0.028 m^3\)

\(R = 8.4 \frac{\text{J mole}^{-1}}{K}\)

\(\therefore PV = nRT\)

\(P = \frac{nRT}{V}\)

\(P = \frac{1/2 \times 8.4 \times 300} {0.028}\)

\(P = 45000 \ N/m^2\)

\(P = 45\times 10^3 \ N/m^2\)