Order Of Reaction

(ii) 1-chlorobutane (iii) But-1-ene

Step 1: For a zero-order reaction, the rate equation is: Step 2: The unit of velocity (rate of reaction) is: Step 3: The unit of rate constant for a zero-order reaction is:

Step 1: The rate of reaction is given by: where is the order of the reaction. Step 2: Since the volume is doubled, the concentration is halved: Step 3: The rate is also halved: Step 4: Comparing, Thus, the order of reaction is **1**.

Step 1: The integrated rate law for a first-order reaction is: Step 2: For half-life, at , : Step 3: When 3/4 of the reaction is complete, : Thus, the time taken for 3/4 completion is twice the half-life.

The order of a reaction refers to the sum of the exponents of the concentrations of the reactants in the rate law. The order indicates how the rate of reaction is affected by the concentration of the reactants.
1. For the first velocity equation :
The total order of the reaction is the sum of the exponents of the concentrations of the reactants. In this case, the exponents are 1/2 for A and 3/2 for B. Therefore, the total order is:
2. For the second velocity equation :
Similarly, the total order of the reaction is the sum of the exponents of the concentrations of the reactants. Here, the exponents are 3 for A and -1 for B. Therefore, the total order is:
Thus, for both reactions, the total order is 2.

Definition of order of reaction:
The order of a reaction is the sum of the powers of the concentrations of the reactants in the rate law expression of the reaction.
It indicates how the rate of reaction depends on the concentration of the reactants.
General reaction:

The rate law for this reaction can be written as:

Where:
- = rate constant,
- = order of reaction with respect to A,
- = order of reaction with respect to B.
Overall order of reaction:

Experimental determination:
The values of and are not necessarily equal to the stoichiometric coefficients and .
They are determined experimentally using methods such as:
1. Initial rate method: By measuring the rate of reaction for different initial concentrations of A and B, the powers and are calculated.
2. Integrated rate equations: By analyzing the concentration of reactants as a function of time, the order of reaction can be established.
Thus, the order of reaction of is given by the sum of experimentally determined powers .