Question

Can ferric(3) oxide or ferric(3) acetate be substituted with ferric(3) chloride for phenol test ?

Can ferric(3) oxide or ferric(3) acetate be substituted with ferric(3) chloride for phenol test ?

Answer 1

I don't think ferric oxide and ferric acetate can be substituted with `FeCl_3`, as they are insoluble in water.

Explanation:

The reaction between phenol and ferric chloride is
`6C_6H_5OH + FeCl_3 -> H_3[Fe(OC_6H_5)_6] + 3HCl`.

Then, why do I think ferric oxide and ferric acetate is inappropriate?

・Ferric oxide(`Fe_2O_3`) is insoluble in water.
・Ferric acetate(`[Fe_3O(OAc)_6(H_2O)_3]OAc`, where `Ac=CH_3COO^-`) is a coordination compound itself. It is also insoluble in water.