## 0 order

$\frac{d[R]}{dt}=-k; [R]=-kt + [R]_{0}; t_{\frac{1}{2}}=\frac{[R]_{0}}{2k}$

Jasmine Fendi 1D
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### 0 order

What would be an applicable example of a 0 order reaction? When would that make sense?

Ruby Tang 2J
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Joined: Fri Aug 30, 2019 12:15 am

### Re: 0 order

An example of a zero order reaction is the decomposition of nitrous oxide in the presence of a hot platinum wire (a catalyst): 2N2O --> 2N2 + O2. Generally, a reaction involving a catalyst will be zero order. Using the stated reaction as an example, if we were to increase the concentration of the reactant, N2O, up to a certain point the reaction rate wouldn't change anymore. The reason for this is that there is only so much catalyst available, and once the catalyst is saturated with reactant (ie all of the catalyst is in contact with a reactant molecule), then the reaction can't get any faster. This is why we say that for zero order reactions, rate = k. It's important to also remember that a zero order reaction is only zero order as a result of the reaction begin carried out under a specific set of conditions: the reactant will eventually be exhausted, and therefore the rate cannot be equal to k forever. Before the reactant is completely depleted, the reaction will revert to a different rate law.

205405339
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Joined: Thu Jul 11, 2019 12:16 am

### Re: 0 order

zero order means concentration of reactants has no effect on rate so if trial 1 had the same concentration of reactant a but had twice the concentration of reactant b compared to trial 2, trial 1 will still have the same rate as trial 2. essentially rate is unaffected by the change in reactant concentrations

Callum Guo 1H
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### Re: 0 order

nicole-2B
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### Re: 0 order

Jacob Motawakel
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### Re: 0 order

zero order means k is a constant, and it is not changed by differences on concentration of reactants. The rate law is just equal to k.

Jainam Shah 4I
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Joined: Fri Aug 30, 2019 12:16 am

### Re: 0 order

Also, when a catalyst is present the reaction can be zero order, because the catalyst controls the reaction rather than the concentration or amount of reactant present making the reactants a negligible part of the reaction.

William Chan 1D
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### Re: 0 order

A 0 order reaction occurs when the concentration of the reactant doesn't matter. This most often happens when there is a catalyst present, and when the catalyst is catalyzing the reaction at "max" rate already, changing the concentration won't affect the overall reaction rate.

Oduwole 1E
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### Re: 0 order

Jasmine Fendi 1D wrote:What would be an applicable example of a 0 order reaction? When would that make sense?

When it is zero order, it means that the k value is a constant. The rate law would be equal to k.