[37 p194]—This is done in the hood because it has the potential to generate poisonous vaporized mercury. In a small flask is placed 15.2g of pure sodium metal with no stirbar. Sodium metal is explosive when put in contact with water. The sodium is immediately covered with about 100ml of toluene and slowly heated on the hotplate. Near a temperature of around 50°C the metal will melt in the hot toluene and at this point 750g of mercury are added drop by drop. The first few drops will cause violent bubbling of the toluene but this will diminish as the addition continues. When addition is complete, the chemist decants most of the toluene leaving just enough to cover the molten catalyst so that it will not degrade by exposure to the air. Now, while still hot, the toluene/amalgam mix is poured into the container the chemist wishes to store it in, the rest of the toluene is decanted and the air space flushed with nitrogen before sealing the container. The amalgam the chemist made is one of 2% strength.
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