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Consider the reaction : Cl₂(aq) + H₂S(aq) → S(s) + 2H⁺(aq) + 2Cl⁻(aq) The rate equation for this reaction is rate = k[Cl₂][H₂S] Which of these mechanisms is/are consistent with this rate equation? A. Cl₂ + H₂S → H⁺ + Cl⁻ + Cl⁺ + HS⁻ (slow) Cl⁺ + HS⁻ → H⁺ + Cl⁻ + S (fast) B. H₂S ⇌ H⁺ + HS⁻ (fast equilibrium) Cl₂ + HS⁻ → 2Cl⁻ + H⁺ + S (slow)

1. A only
2. Both A and B
3. Neither A nor B
4. B only

Correct answer: Neither A nor B

Solution

Both proposed mechanisms do not align with the rate equation, as they introduce intermediates or steps that do not reflect the direct dependence on the concentrations of Cl₂ and H₂S as indicated by the rate law. Therefore, neither mechanism is consistent with the observed rate equation.

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