Question

Select the rate law that corresponds to the data shown for the following reaction :$A+B\to C$
Exp. [A] [B] Initial rate
1. 0.012 0.035 0.10
2. 0.024 0.070 1.6
3. 0.024 0.035 0.20
4. 0.012 0.070 0.80

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

Answer 1

The correct option is C $Rate=K\left[A\right]K[B{]}^3$

From experiments 1 and 3, it can be observed that when the concentration of B is kept constant and the concentration of A is doubled, the initial rate
of reaction is doubled. Hence, the order of the reaction w.r.t A is 1.
From experiments 1 and 4, it can be observed that when the concentration of A is kept constant and the concentration of B is doubled, the initial rate
of reaction becomes eight times. Hence, the order of the reaction w.r.t A is 3.
Hence, the rate law equation is $Rate=K\left[A\right]K[B{]}^3$