The principles of theoretical chemistry : with special reference to the constitution of chemical compounds / by Ira Remsen.

  • Remsen, Ira, 1846-1927.
Date:
1893
Catalogue details

Licence: Public Domain Mark

Credit: The principles of theoretical chemistry : with special reference to the constitution of chemical compounds / by Ira Remsen. Source: Wellcome Collection.

Provider: This material has been provided by University of Bristol Library. The original may be consulted at University of Bristol Library.

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    nized Avas the Imo of the indestructibility of matter. It was found as the result of many observations that the sum of the masses of the products of a chemical change is always exactly equal to the sum of the masses of the sub- stances which act upon one another. Nothing is gained or lost in the operation. This law, like every other law of nature, is simply a statement of what has been .found to be true in every case that has been studied, and its statement implies that a large number of cases have been studied. Since its truth was first recognized, an almost infinite number of observations have confirmed it in the most striking way. As regards the question whether it is possible to conceive of a state of things in which the law of the indestructibility of matter would not hold good we have nothing to do. It may be said, however, that the law could not have been discovered without the aid of many quantitative chemical experiments. It is an expression of facts established. It is not an axiom. The next law discovered was the law of definite pro- portions; and almost at the same time came the law of multiple j^roportions. These two laws are the expressions of the facts learned in studying the proportions in which the elements combine with one another. The discovery of a law naturally leads to a desire to explain it When we have recognized that elements com- bine according to the laws of definite and multiple propor- I tions, we next ask, Why do they combine in this way? An attempt to answer this question leads to some sug- gestion which is known as an hypothesis. If, after it has been thoroughly tested by further extensive study of the facts, the hypothesis is found to be in harmony with all the facts, and capable of explaining them, it is then called a theory. The atomic hypothesis was put forward to ex- ^ plain the laws of definite and multiple proportions, and this hypothesis has proved of great value in enabling chemists to deal with the facts of chemistry. It has long since been accepted as a satisfactory theory. Besides the laws mentioned several others bearing upon the proportions by weight or by volume in which sub- stances act upon one another have been discovered, and all have been found to be explicable by the aid of the atomic hypothesis. Among them may be mentioned the law of combination by volume, the law of specific heats, and,