When a solution of mixture having two inorganic salts was treated with freshly prepared ferrous sulphate in acidic medium, a dark brown ring was formed whereas on treatment with neutral FeCl 3 , it gave deep red colour which disappeared on boiling and a brown red ppt was formed. The mixture contains

Step-by-step solution

The brown ring test is a typical nitrate test that involves adding iron(II) sulphate to a nitrate solution, then slowly adding strong sulfuric acid until the acid forms a layer below the aqueous solution. The existence of the nitrate ion will be shown by the formation of a brown ring at the junction of the two layers. Dark brown ring is formed in the confirmatory test of NO 3 - − ions. Deep red precipitate with FeCl 3 is formed in the presence of CH 3 COO - ions.