Preparation of zinc amalgam
In order to obtain a homogeneous zinc amalgam, it is advisable to shake or stir the mixture during the amalgamation. The quality of the amalgam can be improved by three washings of the zinc with hot hydrochloric acid twice before amalgamation. A mixture of 100 g of mossy zinc, 5 to 10 g of mercuric chloride, 5 ml of concentrated hydrochloric acid, and 100 to 150 ml of water is stirred or shaken for five minutes. The aqueous solution is decanted, and the amalgamated zinc is covered with 75 ml of water and 100 ml of concentrated hydrochloric acid.
Organic Reactions, Volume 1, 163, (1942).