JAMB - Chemistry (2025 - No. 48)
The correct arrangement of gases in the order of increasing rate of diffusion is
[H = 1, C = 12, N = 14, O = 16, S = 32]
Wyjaśnienie
According to Graham's Law of Diffusion, the rate at which a gas diffuses is inversely proportional to the square root of its molar mass. Therefore, gases with lower molar masses diffuse faster than those with higher molar masses. For the rate of diffusion to increase, the molar masses of the gases must decrease in the sequence listed.
The molar masses for the gases in option B are calculated using the provided atomic weights (H=1, O=16, N=14, S=32):
SO\(_2\)= 32 + (16 x 2) = 64 g/mol
O\(_2\)= 16 x 2 =32 g/mol
NH\(_3\) = 14 + (1 x 3) = 17 g/mol
H\(_2\) = 1 x 2 = 2 g/mol
The order of molar masses is 64 g/mol > 32 g/mol > 17 g/mol > 2 g/mol. Since the molar masses decrease in this sequence, the rate of diffusion increases.
The correct arrangement of gases in the order of increasing rate of diffusion is B.