Question

Question #37a30

Answer 1

See below.

Explanation:

Let us assume that the reaction is under the following general form:

`A+B->C`

The rate law is determined experimentally to be:

`R=k[A][B]^2`

The rate law with the first concentrations could be written as:

`R=k[A_1][B_1]^2`

If the concentration of `A` is doubled, this means that the new concentration is: `[A_2]=2xx[A_1]`

and the concentration of `B` is tripled: `[B_2]=3xx[B_1]`

Replacing the new concentration in the expression of the rate law: `R'=k[A_2][B_2]^2`

Therefore, we have:
`R'=k[A_2][B_2]^2=k(2xx[A_1])(3xx[B_1])^2`

`=>R'=(2)(3)^2xxunderbrace(k[A_1][B_1]^2)_R`

`=>R'=(2)(3)^2xxR`

`=>R'=2xx9xxR`

`=>R'=18xxR`

Which indicates that the rate of the reaction will increase by a factor of `18`.

Here is a complete lesson on reaction rate:
Chemical Kinetics | Reaction Rates & Rate Law.