Can somebody help me with this College Chem question about coordination compounds?

Question

A compound with formula RuCl3•5 H2O is dissolved in water, forming a solution that is apx the same color as the solid. Immediatly after forming the solution, the addition of excess AgNO3 (aq) forms 2 mol of solid AgCl per mole of complex. Write the formula for the likely compound, showing which ligands are likely to be present in the coordination sphere.


2) afer a solution of RuCl3•5 H2O has stood for about a year, addition of AgNO3 (aq) precipitates 3 mol of AgCl per mole of complex. What has happened in the ensuing time?



Could you please show me the steps, too? (pretend i dont know anything about chem, because for some reason, these questions arent getting along with me.)

Answer 1

If Cl is acting as a ligand, then AgNO3 won't touch it. If Cl- is acting as an anion, then AgNO3 will precipitate it. In the first case, there are 2 Cl- ions as anion, and one as ligand, so the complex ion is going to be [RuCl(H2O)5]2+ , and the compound is RuCl(H2O)5]Cl2.

Afte a year, all the Cl has come out of the complex, having been replaced by water. So we have [Ru(H2O)6]3+ as the ion.