## 15.15

$\frac{d[R]}{dt}=-k[R]; \ln [R]=-kt + \ln [R]_{0}; t_{\frac{1}{2}}=\frac{0.693}{k}$

Gabriela Carrillo 1B
Posts: 53
Joined: Fri Sep 29, 2017 7:04 am

### 15.15

Is the concentration of CH3Br raised to the power of 1.2 in the rate law for the reaction? What does 1.2 imply?

Johann Park 2B
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Joined: Thu Jul 27, 2017 3:01 am
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### Re: 15.15

The concentration increased by a factor of 1.2 means that the rate of the reaction also increases by a factor of 1.2:

1.2Rate = k [1.2CH3Br]x[OH-]y

melissa carey 1f
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Joined: Fri Sep 29, 2017 7:06 am

### Re: 15.15

Since the rate increase is linear to reactant concentration increase, it implies it's first order.

Chloe1K
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Joined: Fri Sep 29, 2017 7:05 am

### Re: 15.15

I think the book just gave a random increase to concentration to show that if rate increases by the same factor it is a first order reaction.

Janine Chan 2K
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Joined: Fri Sep 29, 2017 7:04 am

### Re: 15.15

Doesn't ln[A] vs. time have to be linear to assume it's first order? Or in this case we're just saying that in this question, we can see that multiplying by a factor of 1.2 will increase the rate by a factor of 1.2, which aligns with the first order differential rate law rate = k[A].