Question

Select the law that corresponds to data shown for the following reaction A + B $\to$ Products

Exp.	[A]	[B]	Initial rate
1	0.012	0.035	0.1
2	0.024	0.070	0.8
3	0.024	0.035	0.1
4	0.012	0.070	0.8

• A. Rate = $k[B{]}^3$
• B. Rate = $k[B{]}^4$
• C. Rate = $k\left[A\right][B{]}^3$
• D. Rate = $k\left[A{]}^2\right[B{]}^2$

Answer 1

The correct option is A Rate = $k[B{]}^3$

Exp.	[A]	[B]	Initial rate
1	0.012	0.035	0.1
2	0.024	0.070	0.8
3	0.024	0.035	0.1
4	0.012	0.070	0.8

From experiment (3) and (2), [A] is constant and [B] is doubled and rates becomes 8 time, so order w.r.t [B] = 3.
From experiment (1) and (3), [B] is constant and [A] is doubled, but rate does not change, so order w.r.t [A] = 0. Thus,
rate = $k[B{]}^3$