## Meaning of orders of rate laws

$aR \to bP, Rate = -\frac{1}{a} \frac{d[R]}{dt} = \frac{1}{b}\frac{d[P]}{dt}$

Brooke VanSickle 1J
Posts: 14
Joined: Fri Sep 25, 2015 3:00 am

### Meaning of orders of rate laws

I understand how to calculate the order and how to use them, but I'm a little confused what exactly they mean in relationship of the reaction. Can someone explain what it means for it to be zero, first, or second order in the actual reaction?

Samantha Miceli 3J
Posts: 20
Joined: Fri Sep 25, 2015 3:00 am

### Re: Meaning of orders of rate laws

The order specifies what relationship there is between the rate of a reaction and the concentration of a substance. For a first order reaction, the rate is proportional to the first power of the concentration. For second order, the rate is proportional to the second power of the concentration. For zero order, the rate is independent of the concentration, meaning it is constant no matter what the concentration is. On page 619 of the textbook, there are some graphs that are helpful for visualizing these relationships.