## Reaction Rate

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

Jaira_Murphy_2D
Posts: 31
Joined: Fri Apr 06, 2018 3:00 am

### Reaction Rate

Given a table of rates and concentrations, when you find the rate constant k, is it the same k for all of the other concentrations?

josie 1C
Posts: 18
Joined: Fri Sep 28, 2018 12:19 am

### Re: Reaction Rate

i believe so, as long as it's all the same products and reactants

RachelCheung1A
Posts: 30
Joined: Fri Sep 28, 2018 12:19 am

### Re: Reaction Rate

Yes as long as it is the same formula and under same conditions (ex. temp)

George Ghaly 2L
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Joined: Fri Sep 28, 2018 12:29 am
Been upvoted: 1 time

### Re: Reaction Rate

k is a specific for a certain temperature, so if the reaction takes place at the specified temperature then the k would be the same.

Noah Fox 1E
Posts: 31
Joined: Fri Sep 28, 2018 12:20 am

### Re: Reaction Rate

Wait, I thought initial concentration would be included especially for second order reactions

Yiting_Gong_4L
Posts: 69
Joined: Fri Sep 28, 2018 12:25 am

### Re: Reaction Rate

It is the same k as long as you use the same products and reactants because the numbers they give are under the same temp.

204929947
Posts: 76
Joined: Fri Apr 06, 2018 11:03 am

### Re: Reaction Rate

when given a table, you can use any reaction and the values to kind K, right?

CristinaMorales1F
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Joined: Fri Feb 16, 2018 3:01 am

### Re: Reaction Rate

What is a reaction rate and how does it relate to the rate law?

lukezhang2C
Posts: 59
Joined: Fri Sep 28, 2018 12:18 am

### Re: Reaction Rate

Yes, the K value should be the same for all since you need to use the different concentrations and initial rates in order to find K in the first place.

lukezhang2C
Posts: 59
Joined: Fri Sep 28, 2018 12:18 am

### Re: Reaction Rate

CristinaMorales1F wrote:What is a reaction rate and how does it relate to the rate law?

The reaction rate is the rate of which the reaction proceeds (in M/s) and is related to the rate law as the rate law is used to calculate the initial rates of the reaction. In a problem typically we would use the reaction rate to find the K value, or any missing values from the rate law equation.

lukezhang2C
Posts: 59
Joined: Fri Sep 28, 2018 12:18 am

### Re: Reaction Rate

204929947 wrote:when given a table, you can use any reaction and the values to kind K, right?

Yes, you should be able to use any of the values given to find k as long as they correspond to one another. For example, using random concentrations for an initial rate which was found using other concentrations would not yield a correct answer.