## 1st order reaction

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

Valeria Viera 1B
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### 1st order reaction

What does it mean for a reaction to be first or second order? Did we cover this in 14a or 14b?

Chem_Mod
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### Re: 1st order reaction

The order of a reaction refers to the power to which you have to raise the reactants in a specific chemical reaction to signify how they effect the rate of the reaction. For example, if the rate of the reaction were proportional to [A] (which is the concentration of a reactant labelled A), then this would mean that if you doubled the concentration of reactant A, then the rate would also double, if you quadrupled the concentration of reactant A, then the rate would also quadruple, etc. If the rate of the reaction were proportional to [A]^2, then if you doubled the concentration of reactant A, then the rate of the reaction would quadruple (because 2^2 = 4). In this case the reaction order would be 2 because you have [A]^2. In the first case, the reaction order would be 1 because you have [A]^1=[A].