mustard gas

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mustard gas

mustard gas, chemical compound used as a poison gas in World War I. The burning sensation it causes on contact with the skin is similar to that caused by oil from black mustard seeds. The compound is not a gas but a colorless, oily liquid with a somewhat sweet, agreeable odor; it boils at 217℃. A powerful vesicant, mustard gas causes severe blistering even in small quantities. Highly irritating to the eyes, it quickly causes conjunctivitis and blindness. If inhaled, it attacks the respiratory tract and lungs, causing pulmonary edema. Some effects of exposure to mustard gas are delayed up to 12 hr; death may result several days after exposure. Mustard gas was introduced by the Germans in warfare against the British at Ypres, Belgium, in July, 1917, and took a heavy toll of casualties. It is dispersed as an aerosol by a bursting shell. Chemically, mustard gas is a thioether, 2,2′-dichlorodiethyl sulfide, (ClCH2CH2)2S. It can be prepared by reacting ethylene with sulfur monochloride, S2Cl2, or by other methods. Its vesicant property is readily destroyed either by oxidation or by chlorination (e.g., with bleaching powder).
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The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Mustard Gas


Yperite (β, β′-dichlorodiethyl sulfide), a thio ether of the aliphatic series, S(CH2CH2C1)2; it is poisonous. Mustard gas was first used on July 12, 1917, by the Germans against Anglo-French troops near the Belgian town of Ypres (hence the name yperite).

Mustard gas is a colorless liquid. Melting point, 14.5°C; boiling point, 217°C (with partial decomposition); density, 1.280 g/cm3 (15°C); solubility in water, 0.05 percent. It is readily soluble in organic solvents. Industrial-grade mustard gas is a dark brown, almost black liquid with an unpleasant odor. Mustard gas is hydrolyzed very slowly by water; the rate of hydrolysis increases sharply in the presence of caustic alkalies or upon heating and mixing. It reacts vigorously with chlorinating and oxidizing agents. Since nontoxic products are formed in this case, the above reactions are used for decontamination. Mustard gas forms colored complexes with salts of heavy metals. This property is used for the detection of mustard gas.

Mustard gas is prepared by two methods: (1) from ethylene, CH2=CH2, and sulfur chlorides, such as S2C12 or SCl2; (2) from thiodiglycol, S(CH2CH2OH)2, and hydrochloric acid, HC1. It is a protoplasmic poison. It attacks the skin and eyes in the form of liquid drops, vapor, and mist. Inhalation of the vapor causes grave harm to the upper respiratory tract and the lungs. A characteristic property of mustard gas is the “latent period” (up to 12 hours or more).

Analogous physiological effects are produced by a group of materials of the type RN(CH2CH2C1)2, where R = CH3,C2H5, or CH2CH2C1, which are arbitrarily called nitrogen mustards. The nitrogen mustards are colorless, odorless high-boiling liquids. They are slowly hydrolyzed by water. The hydrolysis is accelerated in the presence of alkalies. The reaction of nitrogen mustards with chlorinating and oxidizing agents generates nontoxic products. These reactions are also used for decontamination. Nitrogen mustards are produced from tertiary β-hydroxyethylamines, RN(CH2CH2OH)2, where R = CH3,C2H5, or CH2CH2OH, by replacing the hydroxyl groups with chlorine atoms. A characteristic feature of nitrogen mustards is their inhibiting action on cell division, in connection with which some nitrogen mustards, as well as their derivatives (such as Embichin and Endoxan), have come to be used in the treatment of malignant tumors.

Gas masks and special protective clothing are used for the protection of the respiratory organs and the skin, respectively.


Soborovskii, L. Z., and G. Iu. Epshtein. Khimiia i tekhnologiia boevykh otravliaiushchikh veshchestv. Moscow, 1938.
Sartori, M. “Novoe v khimii boevykh otravliaiushchikh veshchestv.” Uspekhi khimii, 1954, vol. 21, part 1, p. 62.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.

mustard gas

[′məs·tərd ‚gas]
(organic chemistry)
HS(CH2ClCH2)2S An oil with density 1.28, boiling point 215°C; used in chemical warfare. Also known as dichlorodiethylsulfide.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

mustard gas

an oily liquid vesicant compound used in chemical warfare. Its vapour causes blindness and burns. Formula: (ClCH2CH2)2S
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005