Beryllium Oxide, BeO

Beryllium Oxide, BeO, obtained by heating the hydroxide, is a white powder which is very refractory and, like alumina, becomes difficultly soluble in acids by heating to redness. It can also be obtained by heating any beryllium salt containing a volatile acid. Concentrated nitric or hydrochloric acid only dissolves it slowly, but concentrated sulphuric acid readily converts it into the anhydrous sulphate. It is reducible by carbon in the electric furnace, and at a lower temperature if copper is present. Fluorine vigorously converts it into the fluoride. It melts at 2450° ± 56° C., and is very volatile near its melting-point.

When beryllia fuses and volatilises in the electric furnace it cools to hexagonal crystals that are slightly harder than corundum and are isomorphous with zinc oxide. It can also be crystallised from fused alkali silicates. At 4° C. its density is about 3; between 0° C. and 100° C., its specific heat is 0.247, and it is diamagnetic.

Parsons refers to a " light and feathery " oxide of beryllium which he obtained by heating a dry mixture of beryllium and ammonium chlorides. Beryllia obtained by strongly igniting the hydroxide is distinctly hygroscopic. In high vacuo beryllia gives a blue fluorescence.

Parsons was unable to obtain the blue oxide from the ignition of the hexahydrated sulphate reported by Levi-Malvano.