Preparation of barium nitrite
50 g of lead(II) acetate are dissolved in 200 ml of hot water and 5 ml of glacial acetic acid and cooled to 40-50° C. Then 3.5 g of magnesium ribbon is introduced in coils, each about one foot long. The temperature range is maintained by heating on the steam bath until no more gas is evolved (about one-half hour) and the ribbon is kept com pletely immersed by means of a bent glass rod resting lightly on the metal. To avoid compacting the lead sponge, the reaction mixture should not be shaken. Now the super natant liquid is decanted and the sponge washed gently several times by decantation with hot water. A solution of 10 g of barium nitrate in 100 ml of warm water is poured over the lead and the mixture is gently boiled for 1.5-2 hours. A watch glass is used as a cover to keep the volume constant. The lead(I) oxide is cooled and filtered off. It is then washed with 10 ml of cold water, and carbon dioxide is passed into the reheated filtrate for 5-10 minutes to precipitate a small amount of lead and barium carbonates. The solution is cooled and refiltered. The filtrate is then concentrated, first over a flame to 40 ml, and finally on the steam bath to a pale yellow sirup which solidifies almost completely on cooling. The residue is triturated with 25 ml of acetone and suction-filtered. The crystals are then digested for one-half hour under reflux with 120 ml of 95% alcohol and 30 ml of water, filtered hot, and evaporated. Two crops of crystals are collected, washed with acetone, and dried over calcium chloride. The yield of barium nitrite is 6-7 g. The barium nitrite is slightly deliquescent and should be kept in tightly sealed containers.
Inorganic laboratory preparations, by G. G. Schlessinger, 34-35, 1962
Barium nitrite, barium dinitrite, 13465-94-6, Nitrous acid, bariumsalt, hydrate (9CI), BARIUMNITRITE, barium(2+) dinitrite, ACMC-1BUJM, Nitrous acid, barium salt, AC1L4YR2, CTK4A9236, BARIUM(2+) ION DINITRITE, UNII-5N5G361962, Nitrous acid, barium salt (2:1), EINECS 236-709-9, 5531AF, AR-1H7748, IN000869, IN006615, IN009890, 5N5G361962
Barium nitrite hydrate, CID166820, 115216-77-8, 13596-35-5, 7787-38-4