Preparation of Magnesium Chloride Hexahydrate

Put a small amount of the magnesium chloride hexahydrate into a crucible and roast it. What is observed Decompose the salt completely. How can you see that this has occurred Cool the crucible and add 1-2 ml of water. What is the composition of the substance that has not dissolved in the water  

Preparation of Anhydrous Magnesium Chloride, a. Thoroughly stir magnesium chloride hexahydrate with ammonium chloride, (take the substances in a proportion of 1 2 by mass, respectively), put the mixture into a crucible, and roast it in the flame of a gas burner. Cool the crucible in a desiccator (why ). 

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