Nickel Arsenites

Nickel Orthoarsenite, Ni₃(NaO₃)₂, is formed when a mixture of nickel oxide and arsenious oxide is heated to about 465° C. It is obtained as a bright green amorphous precipitate by the addition of a solution of sodium metarsenite to aqueous nickel nitrate. If an alkali orthoarsenite or tetrarsenite is added to a solution of a nickel salt, the tetrarsenite, Ni₃As₄O₉, is obtained as a light-green precipitate. Both salts are decomposed by heat with loss of arsenious oxide. A basic salt of composition 14NiO.As₂O₃ has also been described.