Identifying Zero vs. First vs. Second Order Reactions

[EllieSchmidtke_4I]

How can you identify zero, first, and second order reactions?

[Ryan 1K]

If given their graphs, you can see which graph provides a straight line based on the axes (ln [A] vs vs [A]). If given their rate laws or chemical equations, you can see how many molecules are involved in each reaction (molecularity).

[chari_maya 3B]

In zeroth order, rate is independent of concentration of reactant so long as it is present in some quantity, in first rate is linearly dependent etc.

[Chris Charton 1B]

You can do so by looking at the graphs produced by modeling the system as 0th, 1st or 2nd order. Which ever order produces a straight line is the correct order.

[Kayli Choy 2F]

If you are given rate constants, you can also figure out whether a reaction is zero, first, or second order:
zero order: k = M/time
first order: 1/time
second order: 1/ (M * time)

[Leonardo Le Merle 1D]

Also, if you are given various rates provided reactant concentrations, and rate does not change as a reactant concentration is increased or decreased, you know it is zeroth order. If it changes proportionately, it is first. If it changes exponentially, it is second or third or above.

[Tanmay Singhal 1H]

once you start becoming more comfortable with the problems you will notice trends that allow you to determine the reaction order

[Myka G 1l]

In a first order reaction, the rate of reaction is directly proportional to the concentration of a single reacting substance. Whereas in a 2nd order reaction the rate depends on the concentration of 2 reacting first order substances or a single reactant with a squared concentration. Because it depends on a single substance, the graph of a first order reaction is a straight line. For a zeroth order reaction the rate is solely dependent on the rate constant.