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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    vapours will be given off, and will collect on the cold sides of the glass in the form of a brownish tarry liquid. Exp. 2.—Place in a test-tube as much mercuric oxide, or red oxide of mercury, as will cover a sixpence, and heat the end of the tube in the flame of a spirit lamp. Oxygen gas will come off as a colourless gas, in which a splinter of wood, previously kindled and int>roduccd into the tube, will burn brilliantly, and drops of metallic mercury will collect on the cold sides of the tube. Such bodies as \vood and mercuric oxide are said to admit of being decomposed, that is, they may be separated into two or more distinct kinds of material ; and all sub- stances which thus admit of being ana/yscil or pulled asunder into their constituent substances are known chemi- cally as compounds. In many cases the chemist can not only separate a cont- pound into its elements, but he can, out of those elements, by synthesis, or putting them together again, build up the compound—as may easily be done w'ith the iron rust, and the mercuric oxide just mentioned. When a body can be thus separated into its elements, and can be re- ])roduced by combining those elements again with each other, we possess the most complete proof of its chemical coni])osition, though much remains to be discovered respect- ing the mode in w'hich the different substances are arranged in the comi^ound. We may know, for example, what letters are wanted to spell a particular word, but in order to spell the word correctly we must also know the order in which these letters are to follow one another. Just so it is necessary to discover if possible the arrangement of the elements in a chemical compound before we can be said truly to know its constitution. Every material object with which we are accpiainted is, in a chemical point of view, either an element or a compound, or else a mechanical mix- ture of two or more elements or compounds. By far the greater number of natural objects are com- B 2