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For the non-stoichiometric reaction 2A + B → C + D, the following kinetic data were obtained in three separate experiments at 298 K.
Initial Concentration (A) | Initial Concentration (B) | Initial rate of formation of C (mol L S)
0.1 M | 0.1 M | 1.2 × 10⁻³
0.1 M | 0.2 M | 1.2 × 10⁻³
0.2 M | 0.1 M | 2.4 × 10⁻³
The rate law for the formation of C is -
- dc/dt = k[A]²[B]
- dc/dt = k[A][B]²
- dc/dt = k[A]
- dc/dt = k[A][B]
Correct answer: dc/dt = k[A]
Solution
The correct option indicates that the rate of formation of C is directly proportional to the concentration of A only, as evidenced by the data showing that varying the concentration of B does not affect the rate when A is held constant. This suggests that the reaction is first-order with respect to A and zero-order with respect to B.
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