Coordination number question.?

Question

please help me with this question, don't be skimpy on the information, as why and how is as important as the answer it self. i can use as much help as i can get! thanks!

A certain complex of metal M is formulated as MCl3*3H20. The coordination number of the complex is not known, but is expected to be 4 or 6.

a) would reaction of the complex with AgNO3(aq) provide information about the coordination number?

b) would conductivity measurements provide information about the coordination number?

Answer 1

a. yes - if any Cl- ions are present (as anions rather than ligands) the co-ordination number is 4.  A white precipitate will give this away.

b. A + ion (co. no. = 4) will have a different conductivity to a 3+ ion (co. no. = 6).