Sodium hexanitritocobaltate(III) is an
inorganic compound
An inorganic compound is typically a chemical compound that lacks carbon–hydrogen bondsthat is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as ''inorganic chemistry''.
Inorgan ...
with the formula . The anion of this yellow-coloured salt consists of the
transition metal nitrite complex . It was a reagent for the qualitative test for
potassium
Potassium is a chemical element; it has Symbol (chemistry), symbol K (from Neo-Latin ) and atomic number19. It is a silvery white metal that is soft enough to easily cut with a knife. Potassium metal reacts rapidly with atmospheric oxygen to ...
and
ammonium
Ammonium is a modified form of ammonia that has an extra hydrogen atom. It is a positively charged (cationic) polyatomic ion, molecular ion with the chemical formula or . It is formed by the protonation, addition of a proton (a hydrogen nucleu ...
ions.
Synthesis and reactions
The compound is prepared by oxidation of cobalt(II) salts in the presence of
sodium nitrite
Sodium nitrite is an inorganic compound with the chemical formula . It is a white to slightly yellowish crystalline powder that is very soluble in water and is hygroscopic. From an industrial perspective, it is the most important nitrite sa ...
:
:
Application for analysis of potassium
Although the sodium cobaltinitrite is soluble in water, it forms the basis of a quantitative determination of potassium, thallium, and ammonium ions. Under the recommended reaction conditions the insoluble double salt, is precipitated and weighed.
In
geochemical analysis, sodium cobaltinitrite is used to distinguish alkali feldspars from plagioclase feldspars in thin section.
See also
*
Potassium hexanitritocobaltate(III)
References
{{Sodium compounds
Cobalt complexes
Sodium compounds
Chemical tests
Inorganic compounds
Coordination complexes
Nitrites