Answer :
(1) The initial rate when [A] is halved and [B] is tripled is, 0.288 M/s
(2) The initial rate when [A] is tripled and [B] is halved is, 0.096 M/s
Explanation:
The given rate law expression is:
![Rate=k[A][B]^2](https://tex.z-dn.net/?f=Rate%3Dk%5BA%5D%5BB%5D%5E2)
Now we have to determine the initial rate when [A] is halved and [B] is tripled.
The new rate law expression will be:
![Rate=k\times (\frac{[A]}{2})\times (3\times [B])^2](https://tex.z-dn.net/?f=Rate%3Dk%5Ctimes%20%28%5Cfrac%7B%5BA%5D%7D%7B2%7D%29%5Ctimes%20%283%5Ctimes%20%5BB%5D%29%5E2)
![Rate=k\times (\frac{[A]}{2})\times 9\times [B]^2](https://tex.z-dn.net/?f=Rate%3Dk%5Ctimes%20%28%5Cfrac%7B%5BA%5D%7D%7B2%7D%29%5Ctimes%209%5Ctimes%20%5BB%5D%5E2)
![Rate=k\times (\frac{9}{2})\times [A]\times [B]^2](https://tex.z-dn.net/?f=Rate%3Dk%5Ctimes%20%28%5Cfrac%7B9%7D%7B2%7D%29%5Ctimes%20%5BA%5D%5Ctimes%20%5BB%5D%5E2)
Given:
Initial rate = 0.0640 M/s
As, Initial rate =
= 0.0640 M/s
Thus,


Now we have to determine the initial rate when [A] is tripled and [B] is halved.
The new rate law expression will be:
![Rate=k\times (\frac{[B]}{2})^2\times (3\times [A])](https://tex.z-dn.net/?f=Rate%3Dk%5Ctimes%20%28%5Cfrac%7B%5BB%5D%7D%7B2%7D%29%5E2%5Ctimes%20%283%5Ctimes%20%5BA%5D%29)
![Rate=k\times (\frac{[B]^2}{4})\times 3\times [A]](https://tex.z-dn.net/?f=Rate%3Dk%5Ctimes%20%28%5Cfrac%7B%5BB%5D%5E2%7D%7B4%7D%29%5Ctimes%203%5Ctimes%20%5BA%5D)
![Rate=k\times (\frac{3}{4})\times [A]\times [B]^2](https://tex.z-dn.net/?f=Rate%3Dk%5Ctimes%20%28%5Cfrac%7B3%7D%7B4%7D%29%5Ctimes%20%5BA%5D%5Ctimes%20%5BB%5D%5E2)
Given:
Initial rate = 0.0640 M/s
As, Initial rate =
= 0.0640 M/s
Thus,

