## Order of Reaction

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

Posts: 91
Joined: Fri Sep 28, 2018 12:16 am

### Order of Reaction

Is the order of reaction solely determined by how many reactants are in the reaction? How high of an order should we be prepared to be able to find rates for etc?

Eshwar Venkat 1F
Posts: 32
Joined: Fri Sep 28, 2018 12:22 am

### Re: Order of Reaction

Remember that each reactant has an order with respect to itself as well, which we determine using reaction rate values. Thus, the order of a reaction is the sum of all the exponents (orders) of the reactants.

Elizabeth Gallmeister 1A
Posts: 41
Joined: Fri Sep 28, 2018 12:21 am

### Re: Order of Reaction

And the order could be lower than the amount of reactants, because some reactants may be raised to the zeroth power, whereas others may be raised to higher powers than that.

lindsey_ammann_4E
Posts: 61
Joined: Fri Sep 28, 2018 12:26 am

### Re: Order of Reaction

We should be prepared to find, for the purposes of this class, the zeroth order, first order, and second order. There are orders higher than that, but they are rare and we are not expected to do calculations involving those.

Ethan Baurle 1A
Posts: 33
Joined: Fri Sep 28, 2018 12:19 am

### Re: Order of Reaction

Find the individual orders of each reaction based on how the rate changes with additional initial concentration of the reactants. Each reactant will have its own individual order and then you will take the sum of the orders of the reactants to find the overall order of the reaction.

Sarah Kiamanesh 1D
Posts: 30
Joined: Fri Sep 28, 2018 12:22 am

### Re: Order of Reaction

The number of reactants do play a role in the overall order, as each contributes a certain exponent to the total that is added to derive this number. I believe that Professor Lavelle said that reactions become less common as their rate orders increase, so we should expect reactions to be of orders: 0, 1, 2, and possibly 3.

Vicky Lu 1L
Posts: 60
Joined: Fri Sep 28, 2018 12:18 am

### Re: Order of Reaction

The order of the reaction is determined by the sum of the orders of the reactants. If the rate=k[A][B]^2, A is first order and B is second order, therefore the overall reaction order is third order.