At a certain concentration of H2 and I2, the initial rate of reaction is 4.0 x 104 M / s. What would the initial rate of the reaction be if the concentration of H2 were halved? Round your answer to

Respuesta :

The question is incomplete, here is the complete question:

The rate of certain reaction is given by the following rate law:

[tex]rate=k[H_2]^2[I_2]^2[/tex]

At a certain concentration of [tex]H_2[/tex] and [tex]I_2[/tex], the initial rate of reaction is 4.0 × 10⁴ M/s. What would the initial rate of the reaction be if the concentration of

Answer : The initial rate of the reaction will be, [tex]1.0\times 10^4M/s[/tex]  

Explanation :

Rate law expression for the reaction:

[tex]rate=k[H_2]^2[I_2]^2[/tex]

As we are given that:

Initial rate = 4.0 × 10⁴ M/s

Expression for rate law for first observation:

[tex]4.0\times 10^4=k[H_2]^2[I_2]^2[/tex] ....(1)

Expression for rate law for second observation:

[tex]R=k(\frac{[H_2]}{2})^2[I_2]^2[/tex] ....(2)

Dividing 2 by 1, we get:

[tex]\frac{R}{4.0\times 10^4}=\frac{k(\frac{[H_2]}{2})^2[I_2]^2}{k[H_2]^2[I_2]^2}[/tex]

[tex]\frac{R}{4.0\times 10^4}=\frac{1}{4}[/tex]

[tex]R=1.0\times 10^4M/s[/tex]

Therefore, the initial rate of the reaction will be, [tex]1.0\times 10^4M/s[/tex]