Webster 1913 Edition
acidussour, fr. the root
akto be sharp: cf. F.
Sour, sharp, or biting to the taste; tart; having the taste of vinegar: as, acid fruits or liquors. Also fig.: Sour-tempered.
He was stern and his face as
Of or pertaining to an acid;
A sour substance.
One of a class of compounds, generally but not always distinguished by their sour taste, solubility in water, and reddening of vegetable blue or violet colors. They are also characterized by the power of destroying the distinctive properties of alkalies or bases, combining with them to form salts, at the same time losing their own peculiar properties. They all contain hydrogen, united with a more negative element or radical, either alone, or more generally with oxygen, and take their names from this negative element or radical. Those which contain no oxygen are sometimes called
hydracidsin distinction from the others which are called
☞ In certain cases, sulphur, selenium, or tellurium may take the place of oxygen, and the corresponding compounds are called respectively
selenium acids, or
tellurium acids. When the hydrogen of an acid is replaced by a positive element or radical, a salt is formed, and hence acids are sometimes named as salts of hydrogen; as hydrogen nitrate for nitric acid, hydrogen sulphate for sulphuric acid, etc. In the old chemistry the name
acidwas applied to the oxides of the negative or nonmetallic elements, now sometimes called anhydrides.
Webster 1828 Edition
Sour, sharp or biting to the taste, having the taste of vinegar, as acid fruits or liquors.
1.When taken into the mouth, they occasion the taste of sourness. They are corrosive, unless diluted with water; and some of them are caustic.
2.They change certain vegetable blue colors to red, and restore blue colors which have been turned green, or red colors which have been turned blue by an alkali.
3.Most of them unite with water in all proportions, with a condensation of volume and evolution of heat; and many of them have so strong an attraction for water, as not to appear in the solid state.
4.They have a stronger affinity for alkalies, than these have for any other substance; and in combining them, most of them produce effervescence.
5.They unite with earths, alkalies and metallic oxyds, forming interesting compounds, usually called salts.
6.With few exceptions, they are volatilized or decomposed by a moderate heat.
The old chimists divided acids into animal, vegetable, and mineral - a division now deemed inaccurate. They are also divided into oxygen acids, hydrogen acids, and acids destitute of these acidifiers. Another division is into acids with simple radicals, acids with double radicals, acids with triple radicals, acids with unknown radicals, compound acids, dubious acids, and acids destitute of oxygen.