Question

If one mole of rucl3·5h2o reacts with agno3 to produce two moles of agcl(s), how can the formula rucl3·5h2o be re-written to show the proper coordination sphere?

Answer 1

The formula of the compound will be:
`[Ru(Cl)_1(H_2O)_5]Cl_2`.

Step-by-step explanation:

Coordination sphere is an array of ions or ligands around central atom or or an ion. Ions and ligands linked to central atom forms primary coordination sphere and ions or molecules linked to primary coordination sphere forms secondary coordination sphere.

Given: If one mole of
`RuCl_3.5H_2O` reacts with
`AgNO_3` to produce two moles of AgCl precipitate.

This means that in primary coordination sphere there is a 1 chloride ion and 5 water molecules. And remaining 2 chloride ions present in secondary sphere which are available to react with silver ions of silver nitrate solution.

This why on reaction with silver nitrate 2 molecules or silver chloride are formed.

`[Ru(Cl)_1(H_2O)_5]Cl_2+2AgNO_3(aq)\rightarrow 2 AgCl(s)+[Ru(Cl)_1(H_2O)_5](NO_3)_2(aq)`

The formula of the compound will be:
`[Ru(Cl)_1(H_2O)_5]Cl_2`.