When a co-ordination compound CrCl3.6H2O is mixed with AgNO3, then 2 moles of AgCl get precipitated per mole of the compound. Find the structure of the complex.

ans. [CrCl(H2O)5]Cl2.H2O

my question is, I know that 2Cl​- ions satisfy the primary valencies, but what about the water molecules?
How can we know what are the no. of water molecules required for the hydration of that complex?
plz. explain.!

Dear student

We are given that the compound is CrCl3.6H2O
Also two moles of AgCl get precipitated by the complex., So we know that two Cl atoms will lie outside the complex.
Hence, one Cl atom lies inside the complex.
[CrCl.6H2O].Cl2.  But we know that the complex is octahedral , so there will be six ligands inside the coordination sphere.
thus 5 water molecules remain inside the coordination sphere and one water will remain outside.
the complex becomes :[CrCl(H2O)5]Cl2.H2O


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