Ether

Ether, often called sulphuric ether, is a very mobile liquid of extreme volatility, and possesses a penetrating odour. Its vapour, given off freely at ordinary temperatures, forms with air a highly inflammable and explosive mixture. Great care is therefore required in using this liquid; no light must on any account be brought near it. It does not mix with water, but floats on the surface, although it dissolves in water to the extent of about 10 percent Commercial ether contains water and alcohol along with traces of other impurities. It is seldom necessary to remove the alcohol from it (for varnish-making, etc.), but it can be got rid of by repeatedly shaking the crude ether with water, whereby much ether also is dissolved away. The water present interferes seriously with the use of ether as a solvent for resins, etc., but it may be removed by careful rectification with fused calcium chloride, that substance having previously been allowed to remain in contact with the liquid for a day. A final distillation from a little metallic sodium completes the drying of the ether and also removes, if used in sufficient quantity, the alcohol present.

Great care is necessary in distilling ether to secure, by a current of ice-cold water in the condenser, the condensation of the vapour.