<unk>  <unk>  is a white crystalline oxide. It is obtained from<unk>  or<unk>  compounds by ignition in the air. The sintered<unk>  (beryllia), which is very stable, has ceramic characteristics. It is similar to aluminium oxide (Al2O3), is highly fire resistant (melting point: 2570°C), and has polymorphism.<unk>  was previously called glucina.<unk>  formed at high temperatures (>800°C) is inert but may be easily dissolved in hot aqueous ammonium bifluoride (NH4HF2) or a hot solution of concentrated sulfuric acid (H2SO4) and ammonium sulfate ((NH4)2SO4).
Beryllium oxide
Arsenic trioxide
Methylene diphenyl diisocyanate
Tantalum carbide
Arsenic tribromide
Arsenic pentoxide
Acetylene tetrabromide
Toluene diisocyanate