Derive integrated rate equation for third order reaction
Answers
Explanation:
Zero order reaction: In zero order reaction, the rate of reaction depends upon the zeroth power of concentration of reactants. Zero order reactions are very rarely observed. Some examples of zero order reactions are: thermal decomposition of HI on gold surface, decomposition of gaseous ammonia on a hot platinum surface etc. A general equation for a zero order reaction with rate constant k is derived below:
A → B
Rate = – d[A]dt = k[A]∘
=> – d[A]dt = k
=> d[A] = -k dt
Integrating both sides:
⇒ [A] = -kt + c………………………..(1)
Where, c= constant of integration,
At time, t=0, [A] = [A]0
Putting the limits in equation (1) we get the value of c,
⇒ [A]0 = c
Using the value of c in equation (1) we get,
=> [A] = -kt + [A]0
The above equation is known as integrated rate equation for zero order reactions. We can observe the above equation as an equation of straight line with concentration of reactant on y-axis and time on x-axis. The slope of the straight line signifies the value of rate constant, k.