hydroxyl Chem.
(haɪˈdrɒksɪl)
[f. hydrogen + oxygen) + -yl, repr. Gr. ὕλη matter, stuff.]
The monad radical HO or OH, consisting of an atom of hydrogen in combination with an atom of oxygen, which is a constituent of a vast number of chemical compounds.
| 1869 Roscoe Elem. Chem. xxix. 292 In the foregoing class of primary alcohols the group OH, hydroxyl, is attached to a carbon atom at the end of the chain. 1871 Ibid. 139 One atom of chlorine [is] substituted for the group of atoms OH (termed the radical hydroxyl). 1880 E. Cleminshaw Wurtz' Atom. The. 263 Hydroxyl does not exist; combined with itself it constitutes hydrogen peroxide. 1890 Roscoe Elem. Chem. 159 All the oxy-acids and also the hydroxides..contain the group OH (water minus 1 atom of hydrogen); this group may be considered as a monad radical, and has received the name of Hydroxyl. 1896 I. Remsen Organ. Chem. x. 156 This instability is generally met with in compounds containing two hydroxyls in combination with one carbon atom. |
b. attrib., as hydroxyl group; hydroxyl acid = hydroxy-acid.
| 1881 Athenæum 26 Feb. 303/1 This author..has thus disproved the conclusion that the two hydroxyl groups had different functions. 1886 Syd. Soc. Lex. s.v., Monobasic acids of the series, CnH2nO3, or lactic series..are called hydroxyl acids because they can be simply and easily obtained by replacing the halogen in the mono-substituted fatty acids by hydroxyl. 1896 Liv. Top. Cycl. I. 412 Gun-cotton..is made from the best white cotton by treatment with nitric acid, three hydroxyl groups being replaced by three NO3 groups. |
c. in Comb. indicating the addition or substitution of the group OH in the compound, as hydroxyl-benzol, hydroxylcarbamide or hydroxylurea.
| 1872 Watts Dict. Chem. Suppl. VI. 725 Hydroxyl-urea is decomposed by boiling potash-ley, with evolution of ammonia. 1877 ― Fownes' Chem. (ed. 12) II. 394 Hydroxylcarbamide or hydroxyl-urea, CH4N2O2,..is prepared by adding a strong solution of potassium cyanate to a solution of hydroxylamine nitrate cooled to -10°. 1893 Brit. Jrnl. Photog. XL. 818 Hydroxyl-monohydride is simply..common water. |