Q35 · CSIR-NET Chemistry, June 2015
Paper: CSIR-NET June 2015 · Subject: Physical Chemistry · Chapter: Surface Chemistry · Topic: Surface Chemistry – General · Marks: 2 · Difficulty: Medium
For a reaction on a surface 
At low pressure of H, the rate is proportional to
At low pressure of H, the rate is proportional to(a)$[H_{2}]$
(b)$1/[H_{2}]$
(c)$\left[\mathrm{H}_{2}\right]^{1 / 2}$
(d)$1/[H_{2}]^{1/2}$
Answer
Answer: C ✓ checked by 4AB · confidence high
The source book printed no answer; this one was worked out and checked — see the explanation.
Explanation
H₂ adsorbs dissociatively, so θ = (Kp)^½/(1 + (Kp)^½). At low pressure θ ≈ (Kp)^½ and the rate is proportional to p(H₂)^½.
Study loop for Surface Chemistry