A manual of electro-metallurgy / By George Shaw.

  • Shaw, George
Date:
1844
Catalogue details

Licence: Public Domain Mark

Credit: A manual of electro-metallurgy / By George Shaw. Source: Wellcome Collection.

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    ‘18 and suppose, further, that one part by weight of A, combines with two parts of B, to form a compound, with three of C to form another, and with four of D to form a third. Now, it is found that these numbers not only represent the propor- tions in which these bodies combine with A, but also the proportions in which they combine with each other. For example, if there exist a compound formed by the union of B and C, the proportions of those elements will be repre- sented by the numbers above associated with them,—namely, two of the former and three of the latter, or some multiple of those numbers. Further, the proportion of any one of these elements represented by its number, is chemically equivalent to the proportion of either of the other elements represented by its number: thus, if a compound consisting of three parts of C, and four of D, be decomposed by the addition of the element A, the proportion of this last element requisite for such decomposition is represented by 1, which will com- bine with 3 of C, or 4 of D, and by that combination will liberate 3 of the former, or 4 of the latter, as the case may be. It is evident, then, that 1 of A is equal to—inasmuch as it takes the place of—4 of D or 3 of C in a chemical com- pound, and vice versd. These combining numbers of the various elementary bodies, are called their chemical equiva- lents, and are the numbers placed opposite to them in the table. 36. If we consider with chemists generally, that matter exists in the form of atoms,—that is to say, minute, indi- visible, unalterable particles, then the equivalent numbers of the elements represent the relative weights of their atoms. 37. Many remarkable and interesting relations present themselves in studying the laws of chemical combination ; but it is only to those laws of combination, and those com- pounds, which have immediate reference to electro-metal- lurgy, that attention will be here directed. Electro-metal- lurgy is an art by which metals are reduced from their
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