silicic, a. Chem.
(sɪˈlɪsɪk)
[f. silic-a (or L. silic- silex1) + -ic. Cf. F. silicique.]
Pertaining to, consisting of, or formed from silica. Chiefly in silicic acid, a very weakly acidic substance obtained esp. by the action of acids on solutions of silicates and usu. existing in the form of colloidal solutions which contain H4SiO4 (orthosilicic acid) but consist mainly of polymeric oxyacids derived from this; any of these constituent acids.
| 1817 T. Thomson Syst. Chem. (ed. 5) II. 92 It might therefore be distinguished by the name of silicic acid, which would be more systematic than the term silica. 1857 Miller Elem. Chem., Org. iii. §3 (1862) 188 Every acid forms at least one ether, and some, such as the silicic and boracic, furnish more than one. 1883 Science I. 490/1 The silica was prepared by decomposing silicic flouride with water. 1898 [see lactonitrile s.v. lacto- 2]. 1913 E. Hatschek Physics & Chem. of Colloids v. 41 If a solution of sodium silicate..is decomposed by a slight excess of hydrochloric acid, and the mixture is dialysed until the free acid and the sodium chloride have been removed, there remains in the dialyser a perfectly clear colourless sol of silicic acid. 1955 Sci. Amer. Sept. 65/3 The more volatile or acidic or silicic constituents of the fluid rock beneath the surface may have concentrated in the original uplifts. 1973 E. G. Rochow in J. C. Bailar et al. Comprehensive Inorg. Chem. I. xv. 1409 The relations between silicon dioxide and water are so close..that it often is difficult to distinguish between solutions of silica, solutions of distinct molecular silicic acids, colloidal dispersions of silica, the definite hydrates of SiO2, hydrated silica in general, and silica gel. |