Caesium oxide It is a good electron emitter; however, its high vapor pressure limits its usefulness. Elemental magnesium reduces caesium oxide to elemental caesium, forming magnesium oxide as a side-product: CsO is hygroscopic, forming the corrosive CsOH on contact with water. Caesium oxide Caesium oxide (IUPAC name) or cesium oxide describes inorganic compounds composed of caesium and oxygen. The following binary (containing only Cs and O) oxides of caesium are known: CsO, CsO, CsO, and CsO. Both the oxide and suboxides are brightly coloured. The species CsO forms yellow-orange hexagonal crystals. Caesium oxide is used in photocathodes to detect infrared signals in
Iron(III) oxide Iron(III) oxide Iron(III) oxide or ferric oxide is the inorganic compound with the formula FeO. It is one of the three main oxides of iron, the other two being iron(II) oxide (FeO), which is rare, and iron(II,III) oxide (FeO), which also occurs naturally as the mineral magnetite. As the mineral known as hematite, FeO is the main source of iron for the steel industry. FeO is readily attacked by acids. Iron(III) oxide is often called rust, and to some extent this label is useful, because rust shares several properties and has a similar composition. To a chemist, rust is considered