Question

What is the difference between zero, first, and second order chemical reactions in terms of the form of their rate equation and how can I graph concentration-time data showing which order they are?

Answer 1

rate equations are

1) zero order :

r = k

integrate rate law is

[A]t = -kt + [A]o

comparing it with y = mx + c

now

draw graph of [A] againsit time

if you get a straight line with a negative slope

then the reaction is zero order

2) first order :

r = k [A]

integrated rate law is

ln [A] = -kt + ln [A]o

now

draw a graph of ln [A] vs time (t)

if you get a straight line with a negative slope

then

the reaction is 1st order

3) second order :

r = k [A]^2

integrated rate law is

1/[A] = kt + ( 1/[A]o)

now

draw a graph of 1 /[A] vs time (t)

if you get a straight line with a positive slope

then

the reaction is 2nd order