How to determine is a Reaction is Zero Order

[chrisavalos-2L]

I was wondering how it is possible to determine if a reaction is zero order... I thought that we could do this by seeing how the concentration of each reactant affects the over rate but I do not know how to go about determining this?

[Steven Garcia 1H]

For a zero order reaction, the most important thing to remember is that the rate is INDEPENDENT of the concentration of the reactant (provided there is some). Therefore, you can change the concentration all you want, but the rate will still remain constant. This is how you would be able to determine if it's a zero order reaction. If we changed the concentration of a reactant of a first order or even second order reaction, then we would expect the rate to change as well. However, for zero order reactions, this is NOT the case! The rate simply equals k.

Hope this helps!

[gwynlu1L]

also, if you need to you can take the concentrations at various times during the rxn and see if they have the same rxn rate. Graphing your findings also helps, since for a graph comparing time to [A] is a linear graph with negative slope.