Question

*What is the structure of the oxalate ion? What type of ligand can it be classified? (Hint: oxalate can be more than one type of ligand)

*In the preparation of potassium tris(oxalato)ferrate(III) trihydrate, why is ethanol added to hot solution of product in water? (Suggest reference: Cotton & Wilkinson, 3^rd, 4^th, or 5^th ed.)

Answer 1

Oxalate ligand is a bidentate ligand it donates two pairs of electrons to the metal atom even though it has four oxygen atoms.

Ethanol is added to the solution so that the complex of iron salt can precipitate out since it is less soluble in alcohol than in water.Hence to separate out the complex we have to add ethanol.