Homework Assignment #6

Due February 5, 2018 by 11:10 a.m.

The following mechanism is proposed for a reaction run in aqueous solution. Hydronium ion (H3O+) is a catalyst for the reaction.

[Cr(H2O)6]2+(aq) + [Co(NH3)5Cl]2+(aq) → [(H2O)5Cr–Cl–Co(NH3)5]4+(aq) + H2O(l)

[(H2O)5Cr–Cl–Co(NH3)5]4+(aq) + H2O(l) → [Cr(H2O)5Cl]2+(aq) + [Co(NH3)5(H2O)]2+(aq)

[Co(NH3)5(H2O)]2+(aq) + H3O+(aq) → [Co(NH3)4(H2O)2]2+(aq) + NH4+(aq)

[Co(NH3)4(H2O)2]2+(aq) + H3O+(aq) → [Co(NH3)3(H2O)3]2+(aq) + NH4+(aq)

[Co(NH3)3(H2O)3]2+(aq) + H3O+(aq) → [Co(NH3)2(H2O)4]2+(aq) + NH4+(aq)

[Co(NH3)2(H2O)4]2+(aq) + H3O+(aq) → [Co(NH3)(H2O)5]2+(aq) + NH4+(aq)

[Co(NH3)(H2O)5]2+(aq) + H3O+(aq) → [Co(H2O)6]2+(aq) + NH4+(aq)

[Cr(H2O)5Cl]2+(aq) + H2O(l) → [Cr(H2O)6]3+(aq) + Cl(aq)

a) Write the net reaction associated with the mechanism.

b) Identify the most probable slow step. Explain why you chose this step.

c) Write the rate law for the net reaction. Indicate the order of reaction for each reactant.

Turn in the following on a clean, full sheet of paper (not torn out of a notebook):

Name

Student ID Number

The answers to the questions.