**Consider this initial-rate data at a certain temperature for the reaction described by**

**2NOBr(g) => 2NO(g) +Br2(g)**

**Determine the value and units of the rate constant**

**k =**

**Concepts and reason**

A rate law represents the behavior or nature of a reaction. It describes the relation between the rate of a reaction and the concentrations of reactants.

**Fundamentals**

Rate law for first order reaction is expressed by:

Here,**k** is the rate constant and n is the order of reaction.

**Answer:**

For the reaction,

The initial rates for formation of are:

Consider the rate law; the rate of gas phase decomposition of

This Equation is directly proportional to the concentration of .

Substitute the values for r and 0.600 for reactant in the rate expression in equation 1 as follows:

Substitute the values for r and 0.750 for reactant in the rate expression for equation 2 as follows:

The value and unit of rate constant is k is

Substitute the values of first two equations in the rate expression then, divide the equation to carried out the order of reaction (n). Put the value of n in the first equation of rate expression and the value of k is carried out.