## units of k

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

Karina Kong 2H
Posts: 98
Joined: Thu Jul 25, 2019 12:16 am

### units of k

Could someone explain why there are different units for each order?

Jiyoon_Hwang_2I
Posts: 101
Joined: Sat Sep 14, 2019 12:17 am

### Re: units of k

Its because some of the concentrations are squared or cubed so the units are also squared/cubed

AronCainBayot2K
Posts: 101
Joined: Fri Aug 30, 2019 12:17 am

### Re: units of k

There are different units of k due to the powers involved in concentrations. Units could be more than the power of 1 which would change the unit of k.

TarynD_1I
Posts: 100
Joined: Sat Aug 24, 2019 12:17 am

### Re: units of k

https://users.stlcc.edu/gkrishnan/rateunits.htm
here is a helpful link to organize which units go with each order of reaction!

Maya Gollamudi 1G
Posts: 100
Joined: Thu Jul 25, 2019 12:15 am

### Re: units of k

Depending on the order of each reactant, certain concentrations may be squared, which makes the unit M^2, affecting k.

005206171
Posts: 107
Joined: Wed Sep 18, 2019 12:20 am

### Re: units of k

When you have reactions of different orders, you end up getting mol^n/L^n on the side of k. Since The rate is always mol/Ls, the kr for different orders will change to always cancel out and get mol/Ls for the units of the final answer/rate.