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### Units

Posted: Wed Feb 17, 2016 1:26 pm
Does the rate constant k of zero-order reactions always have the units of mole/L*sec?

### Re: Units

Posted: Wed Feb 17, 2016 2:52 pm
Yes, other ways of writing the same units would be M (molarity)/s or Ms^-1 or mol(L^-1)(s^-1).

### Re: Units  [ENDORSED]

Posted: Fri Mar 11, 2016 12:11 am
An easy way to determine the units of k is to understand that the rate needs to have units of M/s so for 0 order rate=k and therefore k=M/s. for 1st order: rate=k[A] where [A] has the units of M and so when multiplied with k, k must have units of s^-1. For second order rate=k[A]^2 where [A]^2 has units of M^2 so in order to get rate = M/s, k must be M^-1 s^-1.

### Re: Units

Posted: Sat Mar 11, 2017 2:36 pm
Yes, it'll be always M/Sec

### Re: Units

Posted: Sun Mar 12, 2017 6:19 pm
Divide by Molarity for each order essentially

### Re: Units

Posted: Wed Feb 28, 2018 4:37 pm
There's also one using kPA/sec. Does anyone know how kPA relates to the rate of reactions?

### Re: Units

Posted: Wed Feb 28, 2018 9:55 pm
yes because for oth order, the rate law is written as:
rate = k[A]^0
which is equal to rate = k
since the unit for rate = mol/l*s, the unit for k is therefore mol/l*s

### Re: Units

Posted: Wed Feb 28, 2018 10:13 pm
Yes! M/s