give the derivation of zero order.

For zero order reaction, the rate law is :

 

Rate=?d[A]/dt  = k[A]⁰ = k = constant

 

 

Lets take a general reaction:

 
A —————-> P
 

 

If it is a reaction of zero order then we can write,
Rate = -d [A] / dt = k [A] ⁰ = k

 
or, d [A] = – k dt

 
Integrating both sides, we will get:
[A] = – kt + I
Where I is a constant of integration
At, t = 0, [A] = [A] ₀
Therefore, [A] ₀ = I
Substituting this value of I in equation 1, we will get:
[A] = -kt + [A] ₀
kt = [A] ₀ – [A]
k = 1 / t ([A] ₀ – [A])
Hence, the Integrated Rate Expression of Zero Order Reaction is

 

1 / t ([A] ₀ – [A])