Orders and Graphs

[rynnma1L]

Why can't you tell the difference between a first order and a second order reaction on a concentration vs. time graph?

[Kyle_Phong_2J]

First and second order reaction plots have different y-axes and slopes. First order reactions have the y-axis as ln[A] as well as a negative linear slope while second order reactions have the y-axis as 1/[A] and a positive linear slope.

[Katherine_Davila_2F]

First order reactions have a y-axis of ln[A] and an x-axis of time(s), with a slope of -k'.
Second order reactions have a y-axis of 1/[A] and an x-axis of time(s), with a slope of k.

[Shania_Jin_1B]

Hi! So all the other answers talked about the different linear graphs, although the first has the wrong values and second answer has them flipped. In a graph just of concentration vs. time, both a first order reaction and a second order reaction are a downwards exponential curve. The truth is that it’s very difficult to tell the difference between a - ln graph and a 1/x graph simply by looking at the shape. You would be able to tell though if you plugged in specific values to determine the order.