Sodium dihydrogen arsenate pyroarsenate salt NaHAsO. Sodium dihydrogen arsenate Sodium dihydrogen arsenate is the inorganic compound with the formula NaHAsO. Related salts are also called sodium arsenate, including NaHAsO (disodium hydrogen arsenate) and NaHAsO (sodium dihydrogen arsenate). Sodium dihydrogen arsenate is a colorless solid that is highly toxic. The salt is the conjugate base of arsenic acid: In the laboratory, it is prepared in this way, crystallizing from a hot saturated aqueous solution, where it is highly soluble when hot (75.3 g in 100 mL at 100 °C). It is obtained as the monohydrate. Upon heating, solid NaHAsOHO, loses water of crystallization and
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