| Aim | a ) Preparation of double salt of Ferrous Ammonium Sulphate or Potash Alum. b) Preparation of Potassium Ferric Oxalate. |
| Apparatus Required | For experiment (a) Ferrous Sulphate or Potassium Sulphate Ammonium Sulphate or Aluminium Sulphate Distilled water Glass beaker Stirring rod Filter paper Funnel Heat source For experiment (b) Ferric Ammonium Sulphate Potassium Oxalate Distilled water Glass beaker Stirring rod Filter paper Funnel Heat source |
| Theory | Double salts are compounds that contain two different cations and anions in their crystal structure. Ferrous Ammonium Sulphate and Potash Alum are two examples of double salts. In this experiment, we will prepare the double salt of Ferrous Ammonium Sulphate or Potash Alum. Potassium Ferric Oxalate is an inorganic compound used in photography and other applications. In this experiment, we will prepare Potassium Ferric Oxalate. |
| Procedure | Procedure for experiment (a) Weigh out the required amounts of Ferrous Sulphate or Potassium Sulphate and Ammonium Sulphate or Aluminium Sulphate. Dissolve each salt separately in a small amount of distilled water in a glass beaker. Slowly pour the solution of Ferrous Sulphate or Potassium Sulphate into the beaker containing the solution of Ammonium Sulphate or Aluminium Sulphate with constant stirring. Heat the mixture and stir until all the salts have dissolved. Allow the solution to cool slowly and then set it aside for a few hours. Crystals of the double salt will form in the solution. Filter the crystals using filter paper and a funnel. Wash the crystals with cold water to remove any impurities. Dry the crystals by placing them in an oven or in the air. Procedure for Experiment (b) Weigh out the required amounts of Ferric Ammonium Sulphate and Potassium Oxalate. Dissolve each salt separately in a small amount of distilled water in a glass beaker. Slowly pour the solution of Ferric Ammonium Sulphate into the beaker containing the solution of Potassium Oxalate with constant stirring. Heat the mixture and stir until all the salts have dissolved. Allow the solution to cool slowly and then set it aside for a few hours. Crystals of Potassium Ferric Oxalate will form in the solution. Filter the crystals using filter paper and a funnel. Wash the crystals with cold water to remove any impurities. Dry the crystals by placing them in an oven or in the air. |
| Observation and Result | Observation: Crystals of the double salt will form in the solution upon cooling. Result: The double salt of Ferrous Ammonium Sulphate or Potash Alum will be obtained as crystals after filtering and drying. Observation: Crystals of Potassium Ferric Oxalate will form in the solution upon cooling. Result: Potassium Ferric Oxalate will be obtained as crystals after filtering and drying. |