6D.11 (e) & (f)

[Cassidy Kohlenberger 3D]

I know that in AlCl3 and Cu(NO3)2, the Al3+ and Cu2+ are highly charged metal cations, and their pull allows water molecules to pick up another H+ and therefore make the solution more acidic. However, I'm really struggling on writing out equations to demonstrate this. For example, in the solution guide for AlCl3 it shows that Al3+(H20)6 + H20 -> H30+ + Al(H20)5OH2+. For Cu(NO3)2 it also shows Cu2+ binding with 6 water molecules. Why are there 6 water molecules that bind to the aluminum ion...can someone explain?

[Qilan Li 4I]

I don't know if this is extremely helpful but you can refer to Table 6D.1 in the textbook and it shows all the small, highly charged metal cations that are written with (H2O)6. This is how I know when and where to include it.

[asannajust_1J]

octahedral complexes are the most common, so generally they will have 6 water molecules attached.