For a reaction first order in A and first order in B, the rate is 2.4 x 10^-3 mol dm-3 s-1 when [A] = 0.10 and [B] = 0.20 mol dm-3. What is k?
Answer and explanation
Correct answer: B. 0.12 dm3 mol-1 s-1
- Step 1: Rate = k[A][B], so . Step 2. with units dm3 mol-1 s-1 (second order overall). Answer: 0.12 dm3 mol-1 s-1. Why not the others: 0.048 multiplies by instead of dividing by one concentration; 8.3 inverts; 0.12 s-1 gives the unit for a first order rate constant.
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