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### 3rd order?

Posted: Tue Feb 16, 2016 8:13 pm
What is the units for third order rxns?

### Re: 3rd order?

Posted: Tue Feb 16, 2016 8:13 pm
1/M^2s

### Re: 3rd order?

Posted: Sat Mar 10, 2018 12:38 am
I agree

### Re: 3rd order?

Posted: Sat Mar 10, 2018 2:46 pm
If you don't remember the units for k for certain orders you can always just divide the rate by the concentration. For 3rd order reactions, the units are (M/s)(1/M^3) which simplifies to (1/M^2)s

### Re: 3rd order?

Posted: Sat Mar 10, 2018 8:16 pm
What would we be asked about third order reactions other than their units?

### Re: 3rd order?

Posted: Sat Mar 10, 2018 11:15 pm
If you want to write the units of K in terms of molarity, it would be $M^{-2}/s$, but if you wanted to write it in terms of moles and liters, it would be $L^{2}/(mol^{2}s)$.

### Re: 3rd order?

Posted: Fri Mar 16, 2018 2:46 am
If you look at first order and second order reactions, when you increase the order, you raise the power of the L and the mol in the units. Thus as you increase the order further, the power continues to rise.

### Re: 3rd order?

Posted: Fri Mar 16, 2018 7:07 pm
It's very rare for 3rd order rxns to occur unless it's the overall rxn's order. The units are 1/M^2.s