Beryllium Iodide, BeI₂

Beryllium iodide, BeI₂, which is very similar to the chloride, occurs in colourless crystals which melt at about 510° C., boil between 585° C. and 595° C., and sublime very perceptibly below their melting-point. Like the chloride and bromide it forms compounds with ammonia, organic bases, and ether. It is insoluble in most organic solvents except alcohol. It can be sublimed in a current of dry carbon dioxide, hydrogen, or nitrogen. Water reacts violently with it. with the evolution of hydrogen iodide. This sensitiveness to water makes beryllium iodide very unstable in moist air, and the salt is, in general, very reactive towards chemical reagents; oxygen or air, for example, readily decompose it, and it takes fire when heated to near redness in oxygen.

Beryllium iodide was first prepared by acting on beryllium with iodine; but our accurate knowledge of it is largely due to Lebeau, who prepared it in considerable quantity by heating beryllium carbide to about 700° C. in a current of hydrogen iodide containing iodine vapour.