Question

During the kinetic study of the reaction,
2A + B➝ C + D, following results were obtained:

Run [A]/mol L ⁻¹ [B]/mol L ⁻¹ Initial rate of
formation of
D/mol L ⁻¹ min⁻¹
I 0.1 0.1 6.0 × 10⁻¹
II 0.3 0.2 7.2 × 10⁻¹
III 0.3 0.4 2.88 × 10⁻¹
IV 0.4 0.1 2.40 × 10⁻¹
Based on the above data which one of the
following is correct?
(a) rate = k[A]² [B]
(b) rate = k[A] [B]
(c) rate = k A]² [B]²
(d) rate = k [A] [B]²

Answer 1

Answer :- (c) rate = k A]² [B]²

Answer 2

(d) rate = k [A] [B]²

Explanation:

Please refer to the data in the tabular form in the attached picture.

In experiment 1 and 4, Concentration of B is constant, concentration of A is quadrupled and rate is also quadrupled. So order [A] = 1

In experiment 2 and 3, Concentration of A is constant, concentration of B is doubled and rate is quadrupled. So order [B] = 2

So we get r = k[A][B]²  

Option D is the answer.