Potassium arsenite

Potassium acetate, 20 629-630 Potassium acid tartrate, 20 637 Potassium alkoxides, 20 604-605 Potassium a-hydrohexafluoroisobutanoyl fluoride, 13 724 Potassium amides, 20 605 Potassium analysis, of water, 26 31 Potassium arsenite (Fowler s solution), 3 276... 

Potassium arsenate (see Arsenic and arsenic compounds) Potassium arsenite (see Arsenic and arsenic compounds) Potassium bis(2-hydroxyethyl)dithiocarbamate Potassium bromate... 

It is of historical interest that Fowler s solution, which contains 1% potassium arsenite, was widely used as a medicine for many conditions from the eighteenth century through the mid-twentieth century. Organic arsenicals were the first pharmaceutical antimicrobials and were widely used for the first half of the twentieth century until supplanted by sulfonamides and other more effective and less toxic agents. 

Sulphur dioxide when passed through a solution of a thiosulphate gives rise not only to tetrathionate but also to trithionate and penta-thionate.12 Under suitable conditions, however, with a high concentration of sulphur dioxide, the tetrathionate separates. The reaction is accelerated by traces of potassium arsenite.13... 

Potassium Arsenites.—At 25 C. the ternary- system K20-As203— HaO indicates the existence of two arsenites of potassium, soluble in water without decomposition 9 these are potassium tetrarsenite, K2As407, and potassium metatetrarsenite, K8As409.12H20. 

In the Rosenmund synthesis salts of arsonic acids are obtained by treatment of aryl halides with sodium or potassium arsenite.8... 

An arsenite of composition 3CoO. 2As203 is obtained as an amethyst-coloured powder by the interaction of solutions of potassium arsenite and cobaltous nitrate.4 It dissolves in caustic potash to a blue solution ammonia gives a brown colour, and potassium cyanide a yellow. 

Potassium arsenite, K3As03.—The arsenite is very unstable, but from its solution containing excess of arsenious acid potassium hydrogen diarsenite, KHAs204 or K2H2As408, can be isolated by covering it with a layer of alcohol.3... 

Since the time of Tofana arsenic has featured in many cases of poisoning. The availability of various forms of the poison, such as arsenious oxide used in rat poison and weedkiller, and potassium arsenite in flypapers, was probably one reason for its popularity. In England and Wales, for example, of 541 fatal poisonings between 1837 and 1838, 185 were due to... 

---