## Order less than 0

Sue Xu 2K
Posts: 58
Joined: Fri Sep 29, 2017 7:06 am

### Order less than 0

Are there reactions with a order less than 0? For example, the rate law = k [R]^-1

Liz White 1K
Posts: 35
Joined: Thu Jul 13, 2017 3:00 am

### Re: Order less than 0

Yes, a reaction order can be negative. This means that the concentration has an inverse effect on the rate of reaction.

Seth_Evasco1L
Posts: 54
Joined: Thu Jul 27, 2017 3:00 am

### Re: Order less than 0

Also for example, if the rate = k[A]-1 and the concentration of A doubled, then the rate would be halved.

Andrew Nguyen 2I
Posts: 68
Joined: Fri Sep 29, 2017 7:07 am

### Re: Order less than 0

A lot of sources say something like this is too complex to determine if reactants and products are expressed in the rate law; however I would just use the rules we've been taught by adding the powers up as integers, where powers in the denominator are simply negative numbers.

mayapartha_1D
Posts: 50
Joined: Fri Sep 29, 2017 7:07 am

### Re: Order less than 0

Yes, an order can be negative as well as a fraction! But we mainly just focus on zero, first, and second as those are the most common, naturally occurring orders for reactions.