Preparation of Sodium Paramolybdate

Preparation of Sodium Paramolybdate. Pour 20 ml of a sodium molybdate solution into a 100-ml beaker. Heat the solution and introduce freshly precipitated molybdic acid into it in small portions with stirring until it stops dissolving. Filter the solution and evaporate it in a water bath until crystallization of a sample taken begins. 

Examine the crystals under a microscope and compare them with crystals of the initial sodium molybdate. Cool the solution and filter off the product. What is its composition  

Pour the mother liquor into a number of test tubes and add a solution of a calcium, aluminium, or iron salt to each of them. What do you observe Write the equations of the reactions. What is the composition of commercial ammonium molybdate  

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