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EXPERIMENT LT, Aim, To prepare the crystals of potassium ferric oxalate {K3[Fe(C,04)];H20}., Apparatus Required, Three beakers of 100 ml, a glass rod, a china dish, a funnel, filter papers, wash bottles, funnel stand,, sand bath/wire gauze, tripod stand and a burner., Chemical Required, 3.5 g of ferric chloride (anhydrous), 4 g of potassium hydroxide, 5.5 g of potassium oxalate, (hydrated) 4 g of oxalic acid (hydrated), ethanol and distilled water., NOTE If you use hydrated Ferric chloride then take it 6 g., Theory, The addition compounds in which some of the constituent ions or molecules lose their identity and, when they do not break up completely into individual ions, are called coordination compounds., potassium ferric oxalate is a coordinate compound and is prepared by dissolving freshly prepared, ferric hydroxide in the solution of potassium oxalate and oxalic acid. The ppt. of ferric hydro oxide is, obtained by the hydrolysis of aqueous solution of FeCl, with KOH. It is filtered and washed and, then dissolved in an equimolar aqueous solution of potassium oxalate and oxalic acid to obtain pale, green solution. The pale green solution is concentrated to crystallization point to obtain green crystal, of the complex., Chemical Equations :, [FeCl3 (aq) + 3 KOH(aq), → Fe(OH), +3KCI] x 2, 2 Fe(OH), +3C,O,H2.2H,O, → Fe2(C,O4)3 +12H,0, 3C,0,K,H,O+ Fe,(C,O,)3, → 2K3[Fe(C,0,)3l+3H,0, Procedure, 1. Take a clean and dry 100 ml beaker and dissolve 3.5 g of anhydrous ferric chloride in 50 ml of, distilled water., 2. Take 50 ml of distilled water in another clean and dry 100 ml beaker and dissolve 4 g of, potassium hydroxide in it., 3. Now add potassium hydroxide solution into ferric chloride solution in small amount with, constant stirring. Wait for few minutes and then filter the ppt. of ferric hydroxide, (reddish-brown) obtained with the help of a funnel. Wash the ppt. with distilled water.