Foundations of the molecular theory : comprising papers and extracts / by John Dalton, Joseph-Louis Gay-Lussac, and Amedeo Avogadro.

Date:
1893
Catalogue details

Licence: Public Domain Mark

Credit: Foundations of the molecular theory : comprising papers and extracts / by John Dalton, Joseph-Louis Gay-Lussac, and Amedeo Avogadro. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    thollet, who has analysed this salt, obtained by passing carbonic gas into the sub-carbonate, found that it was composed of 73.34 parts by weight of carbonic gas and 26.66 of ammonia gas. Now, if we suppose it to be composed of equal volumes of its components, we find from their known specific gravity, that it contains by weight 71.81 of carbonic acid, 28.19 of ammonia, 100.0 a proportion differing only slightly from the preceding. If the neutral carbonate of ammonia could be formed by the mixture of carbonic gas and ammonia gas, as much of one gas as of the other would be absorbed; and since we can only obtain it through the intervention of water, we must conclude that it is the affinity of this liquid which competes with that of the ammonia to over- come the elasticity of the carbonic acid, and that the neutral carbonate of ammonia can only exist through the medium of water. Thus we may conclude that muriatic, fluoboric, and carbonic acids take exactly their own volume of ammonia gas to form neutral salts, and that the last two take twice as much to form sub-salts. It is very remarkable to see acids so different from one another neutralise a volume of ammonia gas equal to their own; and from this we may suspect that if all acids and all alkalis could be obtained in the gaseous state, neutrality would result from the combination of equal volumes of acid and alkali. It is not less remarkable that, whether we obtain a neutral salt or a sub-salt, their elements combine in simple ratios which may be considered as limits to their propor- tions. Accordingly, if we accept the specific gravity of