## When do we calculate for k

Chew 2H
Posts: 34
Joined: Fri Sep 29, 2017 7:05 am

### When do we calculate for k

I've seen problems that uses k either from the value given in the textbook or by calculating it. how do we know when we calculate for it ourselves and when we simply use the table provided in the textbook?

Cooper1C
Posts: 50
Joined: Fri Sep 29, 2017 7:07 am

### Re: When do we calculate for k

k is based on experimental data, so if you're given data you are probably expected to calculate it. If not, I think you can use the table.

Posts: 32
Joined: Thu Jul 13, 2017 3:00 am

### Re: When do we calculate for k

You can calculate k using integrated rate laws or half life formulas if you are given information about the other variables that are involved (including final and initial concentrations and time/half life). Algebraically isolate k in the formula appropriate for the reactant order and solve.

Alejandra Rios 1L
Posts: 31
Joined: Fri Sep 29, 2017 7:06 am
Been upvoted: 1 time

### Re: When do we calculate for k

If there is a table given, you could use that to find the k value; however, there are cases where the problem will ask you to solve for k and you will have to use the equations we have derived for each reaction and solve for k with the given information. If a problem were to come up and it doesn't directly ask you to solve for k but it is also not given, you can work with the values given to get a k.