Nomenclature
CAS number: 1310-58-3
Potassium hydroxide (K(OH)); potassium hydrate; caustic potash; potassa.
HKO; mol wt 56.11.
H 1.80%, K 69.68%, O 28.51%.
KOH.
Description and references
Prepd industrially by electrolysis of potassium
chloride: Faith, Keyes & Clark's Industrial
Chemicals, F. A. Lowenheim, M. K. Moran, Eds. (Wiley-Interscience,
New York, 4th ed., 1975) pp 674-678. Toxicity: H. F. Smyth et al., Am. Ind. Hyg. Assoc. J. 30, 470 (1969).
Properties
White or slightly yellow lumps, rods, pellets.
Rapidly absorbs moisture and CO2 from the air and deliquesces.
mp about 360°; mp 380° when anhydr.
Corrosive. Keep tightly closed and do not
handle with bare hands. Sol in 0.9 part water, about 0.6
part boiling water, 3 parts alcohol, 2.5 parts glycerol. When dissolved
in water or alcohol or when the soln is treated with an acid, much
heat is generated. A 0.1M aq soln has a pH of 13.5. LD50 orally in rats:
1.23 g/kg (Smyth).Caution
Extremely corrosive. Potential
symptoms of overexposure are irritation of eyes, skin, respiratory
system; eye and skin burns; cough, sneezing; vomiting, diarrhea.
Direct contact may cause painful burns and liquefaction necrosis.
See NIOSH Pocket Guide to Chemical
Hazards (DHHS/NIOSH 97-140, 1997) p 262; Clinical Toxicology of Commercial Products, R. E. Gosselin et al., Eds. (Williams & Wilkins,
Baltimore, 5th ed., 1984) Section III, pp 245-252.Use
Manuf liq soap; mordant for wood; absorbing CO
2; mercerizing cotton; paint and varnish removers; electroplating,
photoengraving and lithography; printing inks; in analytical chemistry
for alkalimetric titrations; in organic synthesis. Pharmaceutic aid
(alkalizer).
Therapeutic Category (Veterinary)
Caustic. In disbudding calves' horns.
In aq solution to dissolve scales and hair in skin scrapings.