Introduction to the study of inorganic chemistry / by William Allen Miller.

  • Miller, William Allen, 1817-1870.
Date:
1871
Catalogue details

Licence: Public Domain Mark

Credit: Introduction to the study of inorganic chemistry / by William Allen Miller. Source: Wellcome Collection.

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    principle remains. Hence it has of late years become the custom further to compare the weights of gases and vapours with the weight of an equal volume of some elementary body ; and the element selected for the purpose is hydrogen, the lightest of all known substances. The result of this comparison with hydrogen will hereafter be spoken of as the relative weight of a gas or vapour. Suppose that, for the ])urpose of this comparison, we take a vessel wliicli would hokl I gram of hydrogen at o” C. and 760 mm. barometer ; the capacity of such a vessel would be 11 -19 litres. This measure, when filled with o.\ygen under similar circumstances, would contain 16 grams of o.xygen; and if filled with nitrogen, it woulfl contain 14 grams of nitrogen. Hence, if the weight of such a bulk of hydrogen be called i, the relative weight of o.xy- gen will be 16, the relative weight of nitrogen 14, and so on, (i i) Acids, Bases, and Salts.—The compounds formed by the union of o.xygen with the other elements differ from each other very much in properties; but among them are two im- portant classes of oxides, chemically op]JOsed to each other, one commonly known as acids, the other as bases. Everyone is familiar with the sourness of vinegar or of a lemon, which in both cases is due to the presence of a substance known ii) chemical language as an acid. The acetic acid gives the sour taste to vinegar ; the citric acid is the substance which gives the sharp flavour to the lemon. There are many other well- known substances, like sulphuric, nitric, and phosphoric acids, which when diluted sufficiently to prevent them from injuring the surface of the tongue, possess a sour taste ; and these all belong to the class of acids. .\gain, most jrersons are accpiainted with the nauseous taste of .soda, and with the peculiar soapy feeling which it occasions when rubbed upon the skin : this is due to what is called the alkaline property of soda, a property in which it resembles potash and a few other substances. The alkalies are soluble in water, and form one class of a numerous group of chemical agents, known tinder the name of bases.