A chemical
reaction in which the product form is further decomposed into another product such
kind reaction of reaction is known as sequential reaction.

If rate
constant of reaction is

**K**and_{1}**K**then the rate of reaction is for the reaction_{2}
For the
determination of concentration of

**A**after time**t**, integrating equation (1)
For the
determination of concentration of

**B**after time**t**,
Net rate of
formation of [B]

Multiply e

^{K}_{2}^{t }to both side^{ }and integrating^{ }
For the
determination of concentration of

**[C]**after time**t**,
Since by law
of mass balance [A]

_{0}=[A]_{t }+[B]_{t}+[C]_{t}
Graphical
representation of concentration of A B and C after time t that is [A]

_{t}, [B]_{t}and [C]_{t }respectively.**Case (1): K**

_{1}>>>K_{2}**Concentration of [B]**when K1>>>K2

_{t}:**in this case we can observed that reaction first (A to B) occurs first and gives nearly to completion before reaction (B to C) take place. Thus nearly all the (A) is converted to the intermediate (B) before any appreciable conversion of (B to C), thus**

**Concentration of [C]**

_{t}:**Graphical representation:**

In general concentration of [A] decreases exponentially, and the concentration of [B] Initially increases up to a maximum and then decrease therefore and concentration of [C] increases steadily until it reaches its final value [A]

_{0}, when all A has changed into [C]**Case (2): K**

_{2}>>>K_{1}**Concentration of [B]**

_{t}:
Since K

_{2}>>>K_{1}then second term in parenthesis rapidly approaches zero while the first term is still near unity consequently concentration of [B] approaches to K_{1}/K_{2}[A] and decay more slowly according to
Since k

_{1}/K_{2 }is very small, the maximum concentration of [B] is much less than [A]_{0 }**Concentration of [C]**

_{t}:**Graphical representation:**

**Calculation of Maximum concentration of [B] and Maximum time:**

**Examples of consecutive reactions:**

**Illustrative Examples:**

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