Nome: oxalic acid; ethanedioic acid
Numero CAS: 144-62-7
Massa molare: 90.03488 g
Percentuale di massa: H 2.2389 %; C 26.680 %; O 71.080 %
Usi / Funzione
• "...is a mild reducing agent and, on this account, is frequently used in the removal of fresh iron rust and ink spots from white cloth, and for bleaching straw hats. It is also used for cleaning copper and brass. Calico printing, dyeing, and tanning are some of the industries using oxalic acid. The fact that oxalic acid is a poison should not be forgotten when the acid is kept in the house and when it is used." 1
• "As analytical reagent; in calico printing and dyeing; for bleaching straw (hats) and leather; removing paint or varnish, rust or ink stains; cleaning wood; manuf[acturing] oxalates; blue ink; celluloid; intermediates and dyes; in metal polishes; in indigo dyeing; in purifying methanol; for decolorizing crude glycerol; for stabilizing hydrocyanic acid. As a general reducing agent; in ceramics and pigments; in metallurgy as cleanser; in the paper industry; in photography; in process engraving; in the rubber mfg industry; in making glucose from starch; as condensing agent in organic chemistry. In vitro blood specimen anticoagulant." 2
• "Oxalic acid has a valuable application as a reducing agent." 3
• "The simplest dibasic organic acid. Its potassium or calcium salt occurs naturally in rhubarb, wood sorrel, and many other plants. It is the strongest ogranic acid and is poisonous. When properly diluted, it removes ink or rust stains from cloth. It is used also as a reagent." 4
Punto di fusione:*
189.5°C †5 = 462.65 K = 373.1°F
189°C 6 = 462.15 K = 372.2°F
1.900 at 17°C 5
* - 1 atm pressure
† - decompone
doppi legami: 2
tripli legami: 0
Sigma Bonds: 7
pi Bonds: 2
carboxyl Gruppi: 2
gruppi idrossilici: 0
(CN)2 (g cyanogen) + 4 H2O (ℓ) → H2C2O4 (aq) + 2 NH3 (g) 7
CaCO3 (s) + 1 H2C2O4 (aq) → CaC2O4 (s) + H2O (ℓ) + 1 CO2 (g) 8
6 HNO3 (aq) + 5 H2C2O4 (aq) + 2 KMnO4 (aq) → 10 CO2 (g) + 2 Mn(NO3)2 (aq) + 2 KNO3 (aq) + 8 H2O (ℓ)
Per maggiori informazioni
(1) - Brownlee, Raymond B., Fuller, Robert W., and Whitsit, Jesse E. Elements of Chemistry; Allyn and Bacon: Boston, Massachusetts, 1959; p 328.
(2) - The Merck Index: An Encyclopedia of Chemicals, Drugs, and Biologicals, 13th ed.; Budavari, S.; O'Neil, M.J.; Smith, A.; Heckelman, P. E.; Kinneary, J. F., Eds.; Merck & Co.: Whitehouse Station, NJ, 2001; entry 6980.
(3) - Estok, George K. Organic Chemistry: A Short Text; W.B. Saunders: Philadelphia, 1959; p 141.
(4) - Taber's Cyclopedic Medical Dictionary, 18th ed.; F. A. David Company: Philadelphia, PA, 1997; p 22.
(5) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 3-154.
(6) - Estok, George K. Organic Chemistry: A Short Text; W.B. Saunders: Philadelphia, 1959; p 138.
(7) - Silberberg, Martin S. Chemistry: The Molecular Nature of Matter and Change 4th ed.; McGraw-Hill: Boston, MA, 2006; p 127.
(8) - Ebbing, Darrell D. General Chemistry 3rd ed.; Houghton Mifflin Company: Boston, MA, 1990; p 138.