Preparation of Potassium Trioxalatochromate III

Preparation of Potassium Trioxalatochromate(III). Dissolve 3 g of potassium oxalate and 7 g of oxalic acid in 100 ml of water. Add 

5 g of potassium dichromate to the solution in small portions with strong agitation. When the reaction terminates, evaporate the solution until almost dry and let it stand for crystallization. Filter off the precipitated crystals and examine them in transmitted and reflected light. Write the equation of the reaction. 

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