Preparation of Magnesium Iodide

In 2-2.5 h after termination of the reaction, decant the solution from the unreacted magnesium into a round-bottomed flask (Fig. 1196) close it with a stopper provided with a stopcock, and cool it in a bath with dry ice. Quench the vacuum created in the flask with argon (nitrogen), using the stopcock of the gas-discharge tube for this purpose. Pour off the mother liquor from the crystals (what is their composition ). If the separated crystals are yellow, recrystallize them from ether. Connect the flask with the crystals to a water-. 

Transfer the magnesium iodide crystals into a weighed weighing bottle and weigh them. Calculate the yield in per cent. 

Apparatus for reacting metallic magnesium (zinc) with iodine in absolute ether (a), and flask for distilling off the solvent (6) 

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