The slowest step is the rate determining step thus the mechanism B will be more consistent because it involve one molecule of H2 and one molecule of ICl. It can be expressed as r=k[H2][ICl] Related Theory The rate determining step in a reaction mechanism is characterised by high activation energy. Usually, the first step is the slow step since it has the highest activation energy.
The reaction of hydrogen and iodine monochloride is given as: H_2(g)+2 ICl_(g) → 2 HCl_(g)+ I_2(g) This reaction is of first order with respect to…
NEET UG 2007 — Chemistry Physical Chemistry
2007mcqeasy
The reaction of hydrogen and iodine monochloride is given as: H2(g)+2ICl(g)→2HCl(g)+I2(g) This reaction is of first order with respect to H2(g) and lCl(g)+ following mechanisms were proposed Mechanism A: H2(g)+2ICl(g)→2HCl(g)+H2(g) Mechanism B: H2(g)+ICl(g)→HCl(g)+HI(g) :slow Hl(g)+lCl(g)→HCl(g)+l2(g); fast Which of the above mechanism(s) can be consistent with the given information about the reaction?
Official previous-year question
Held on 30 Apr 2007 · Verified 9 Jul 2026.
Options
- A
A and B both
- B
neither A nor B
- C
A only
- D
B only
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