Question

The reaction a + 2b 3c occurs in one step in the gas phase. in each blank below, write the exponent of the concentration in the forward rate law or write none if that concentration does not appear in the rate law.

Answer 1

Answer: Exponent of a is 1, exponent of b is 2 and exponent of c = 0

Explanation: Rate law or the rate equation is the expression which relates the rate of the reaction with the concentration of pressure of the reactants. The rate law is expressed in terms of the molar concentration of the reactants with each term raised to power its stoichiometric coefficient in the given reaction.

For general equation:

$A+B\rightarrow C+D$

Rate law expression:

$Rate=k[A]^1[B]^1$

For a given chemical reaction:

$a+2b\rightarrow 3c$

Rate law expression is written as:

$Rate=k[a]^1[b]^2$

• Exponent of a = 1

• Exponent of b = 2

• Exponent of c = 0 (as c is not coming the rate law expression)