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For the parallel reactions of H atoms with HO2: H + HO2 -> H2 + O2 (rate constant k1) H + HO2 -> 2OH (rate constant k2) H + HO2 -> H2O + O (rate constant k3) with k1: k2: k3 = 0.60: 0.30: 0.10, find the molar ratio of products H2 to H2O at time t.

1. 6: 1
2. 3: 1
3. 2: 1
4. 1: 1

Correct answer: 6: 1

Solution

For competing parallel reactions, product amounts are proportional to their rate constants, so H2: H2O = k1: k3 = 0.60: 0.10 = 6: 1.

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