Zinc Ammonium Chloride: Zinc in Spirit of Salt, with Sal Ammoniac

The galvaniser's flux is zinc chloride with sal ammoniac: it dissolves the oxide on the metal and leaves it clean. Dissolve zinc in hydrochloric acid, which gives off hydrogen, then add two parts of sal ammoniac to each part of zinc chloride and dry the salt down. It burns skin and draws water from the air: gloves and goggles, and a closed jar. The picture: zinc chloride, which has drawn water from the air.