\(1000 cm ^{3}\) of gas \(X\) diffused through a porous plug in \(17.32\) seconds. An equal volume of nitrogen under the same conditions took 10 seconds to diffuse through the same porous plug. What is the relative molecular mass of \(X\) ? [N \(=14]\)
A. 16 B. 28 C. 42 D. 84
Correct Answer: D
Explanation
From Graham's law of diffusion, \(\frac{T_{x}}{T_{N_{2}}}=\sqrt{\frac{R \cdot M \cdot M_{X}}{R \cdot M \cdot M_{N_{2}}}}\) \(1.732=\sqrt{\frac{R \cdot M \cdot M_{X}}{28}}\) R.M.M \(M_{X}=28 \times 1.732^{2}\) \(=84\)