Nomenclature
CAS number: 7664-93-9
Oil of vitriol.
H
2O
4S; mol wt 98.08.
H 2.06%, O 65.25%, S 32.69%.
H
2SO
4.
Description and references
Prepd by the Contact Process according to the
reactions 2SO2 + O2 → 2SO3, and SO3 + H2O → H2SO4; by the Chamber
Process according to the reactions 2NO + O2 → 2NO2, and NO2 + SO2 + H2O → H2SO4 + NO. Sulfuric acid of commerce contains 93-98% H2SO4; the remainder is water. Monograph: W. W.
Duecker, J. R. West, The Manufacture of Sulfuric
Acid (Reinhold, New York, 1959) 515 pp. Review of manuf:
Pearce, “Sulphuric Acid: Physico-Chemical Aspects of Manufacture”
in Inorganic Sulphur Chemistry, G. Nickless, Ed. (Elsevier, New York, 1968) pp 535-561; Faith, Keyes & Clark's Industrial Chemicals, F. A. Lowenheim, M. K. Moran, Eds. (Wiley-Interscience, New York,
4th ed., 1975) pp 795-806. Toxicity data: H. F. Smyth et al., Am. Ind. Hyg. Assoc. J. 30, 470 (1969). Review of toxicology and human exposure: Toxicological Profile for Sulfur Trioxide and Sulfuric
Acid (PB99-122038, 1998) 224 pp.
Properties
Clear, colorless, odorless, oily liquid. Corrosive; poisonous. Has a very great affinity
for water, abstracting it from the air and also from many organic
substances; hence it chars sugar, wood, etc. d ≈1.84. bp ≈290°; dec 340° into sulfur trioxide and water. mp 10° (anhydrous acid). 98% H2SO4 freezes at +3°; 93% at 32°; 78%
at 38°; 74% at 44°; 65% at 64°. Misc with water and alcohol with
the generation of much heat and with contraction in vol. When diluting,
the acid should be added to the diluent. Handle
with caution. Keep tightly closed. LD50 orally in rats: 2.14 g/kg (Smyth).Derivative
Sulfuric acid, fuming.
Nomenclature
CAS number: 8014-95-7
Properties
H2SO4 with free SO3, designated in commerce as oleum. Available grades contain up to about 80% free SO3. Colorless or slightly colored, viscous liquid, emitting
choking fumes of sulfur trioxide. Handle with
caution. Corrosive; poisonous. Keep tightly closed in glass-stoppered
bottles.Caution
Potential symptoms of overexposure
are eye, skin, nose and throat irritation; pulmonary edema, bronchitis;
emphysema; conjunctivitis; stomatis; dental erosion; tracheobronchitis;
skin and eye burns; dermatitis. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140,
1997) p 290. See also Clinical
Toxicology of Commercial Products, R. E. Gosselin et al., Eds. (Williams & Wilkins, Baltimore, 5th ed., 1984)
section III, pp 8-12. Occupational exposure to strong inorganic acid
mists containing sulfuric acid is listed as a known human carcinogen:
Report on Carcinogens, Eleventh Edition (PB2005-104914, 2004) p III-234.Use
In manuf of fertilizers, explosives, dyestuffs,
other acids, parchment paper, glue, purification of petroleum, pickling
of metal. Dehydrating agent. Digestion of organic matter. pH modification.
Titration of bases.
Therapeutic Category
Dil acid formerly in treatment of gastric hypoacidity. Concd
acid formerly as a topical caustic.