Ligand substitution reactions

Question 1

Cu2+(aq) and NH3(aq)

Answer 1

[Cu(H2O)6]2+(aq) + 4NH3(aq) –> [Cu(NH3)4(H2O)2]2+(aq) + 4H2O
octahedral pale blue to octahedral dark blue

Question 2

Cu2+(aq) and Cl-(aq)

Answer 2

[Cu(H2O)6]2+(aq) + 4Cl-(aq) –> [CuCl4]2-(aq) + 6H2O(l)

octahedral pale blue to tetrahedral yellow

Question 3

Cr3+(aq) and NH3(aq)

Answer 3

[Cr(H2O)6]3+(aq) + 6NH3(aq) –> [Cr(NH3)6]2+(aq) + 6H2O

octahedral dark green to octahedral purple