Title: Formic Acid
CAS Registry Number: 64-18-6
Additional Names: Ameisensäure (German)
Molecular Formula: CH2O2
Molecular Weight: 46.03
Percent Composition: C 26.09%, H 4.38%, O 69.52%
Line Formula: HCOOH
Literature References: Found in the bites and stings of various insects including bees and ants; metabolite of methanol. Observed by S. Fisher in 1670 in the products resulting from the distillation of ants. Production: P. G. Jessop et al., Nature 368, 231 (1994). Acute and chronic toxicity: G. Malorny, Z. Ernaehrungswiss. 9, 332 (1969). Review of metabolism and toxicology: J. Liesivuori, H. Savolainen, Pharmacol. Toxicol. 69, 157-163 (1991). Clinical trial in treatment of warts: R. M. Bhat et al., Int. J. Dermatol. 40, 415 (2001). Reviews: A. Aguilo, T. Horlenko, Hydrocarbon Process. Int. Ed. 59, 120-130 (1980); D. J. Drury in Kirk-Othmer Encyclopedia of Chemical Technology vol. 11 (Wiley-Interscience, New York, 4th ed., 1994) pp 951-958.
Properties: Colorless liq; pungent odor. bp760 100.8°. mp 8.4°. d20 1.220. pKa (20°) 3.75. nD20 1.3714. Flash point, open cup: 59°C. Surface tension at 20°: 37.67 dyn/cm. Viscosity at 20°: 1.784 cP. Dielectric constant at 20°: 57.9. Vapor pressure at 20°: 33.55 mm Hg. Heat of fusion: 3031 cal/mole; of vaporization at 100°: 104 cal/g. Azeotropic mixture with water: 77.5 wt% formic acid, bp760 107.3°. Strong reducing agent. Misc with water, ether, acetone, ethyl acetate, methanol, ethanol. Partially sol in benzene, toluene, xylenes. LD50 in mice (mg/kg): 1100 orally; 145 i.v. (Malorny).
Melting point: mp 8.4°
Boiling point: bp760 100.8°; bp760 107.3°
Flash point: Flash point, open cup: 59°C
pKa: pKa (20°) 3.75
Index of refraction: nD20 1.3714
Density: d20 1.220
Toxicity data: LD50 in mice (mg/kg): 1100 orally; 145 i.v. (Malorny)
Derivative Type: Spirit of Formic Acid
Additional Names: Spirit of ants
Literature References: Composed of 40 ml of 25% formic acid and 225 ml water in sufficient alcohol to make one liter; corresponds to ~1% formic acid and ~70% abs alcohol by vol.
Properties: Colorless liquid. Miscible with water, alcohol.
CAUTION: Potential symptoms of overexposure are eye, skin, throat irritation; skin burns, dermatitis; lacrimation; rhinorrhea; coughing and dyspnea; nausea. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 148.
Use: Preservative in foods and silage; acidulant in dyeing of natural and synthetic fibers, leather tanning; coagulating latex in rubber production; chemical synthesis.
Therap-Cat: Caustic. |