## 15.3

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

Sammy Thatipelli 1B
Posts: 63
Joined: Thu Jul 27, 2017 3:01 am
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### 15.3

What does it mean when the question asks you to find the unique rate of the reaction? Can someone explain the process to figuring it out? Thanks!

Julianna Thrasher 1B
Posts: 27
Joined: Thu Jul 27, 2017 3:00 am

### Re: 15.3

Unique -average- rate of reaction just means applying the rate law to the given reaction with the stoichiometric coefficients of the substances. All substances can react at different rates so the unique average rate of reaction means choosing one of these rates and diving it by the stoichiometric coefficient of the substance you are using the rate for. You use the same rate of reaction equation, just with added values in the denominator due to diving by the coefficients.

Nishma Chakraborty 1J
Posts: 51
Joined: Fri Sep 29, 2017 7:04 am

### Re: 15.3

Hey Sammy! The unique rate of the reaction is the rate of appearance (products) and disappearance (reactants) divided by the stoichiometric coefficient of a particular species.

The question asking for NO2's unique rate of reaction would be (change in [NO2])/(change in time)*(1/2) (because there are two moles of NO2). There's also a negative sign in front of the answer because NO2 is being consumed/disappearing.

Hope this helps :)