Chemical method, notation, classification, & nomenclature / by Auguste Laurent ; translated by William Odling.

  • Laurent, Auguste, 1807-1853.
Date:
1855
Catalogue details

Licence: Public Domain Mark

Credit: Chemical method, notation, classification, & nomenclature / by Auguste Laurent ; translated by William Odling. Source: Wellcome Collection.

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    j the silicates, phosphates, and arseniates, also certain sub-salts, | orincipally those of the sesquioxides, which appear to have more j complicated formula}, such as 1, 2, 3, 4, 5, 6, 7, 10, 20, . . . . . . . M + 10, 20, 43, 47, 52, 63, 100, and 200 Aq. For the present let us set aside these last bodies, and examine i oure and well crystallised substances only, and we shall then oee, that in nineteen out of every twenty cases, the series of j aydration is M + 1, 2, 3, 4, Aq, and occasionally, (!! M -f 1, 3, and 5Aq. In following out this idea, we require to know whether thcr ; san possibly exist:— 1°. A basic sulphate with this formula: 4 SO3 + 5 M20. 2°. A hydrated sulphate with this : 4 SO3 + 3 M20 + 5 H20. 3°. A hydrobasic sulphate with this: 4 SO3 + 6 M20 + 9 IPO. 4°. Whether the molecule of alum contains 4 SO3, or only I SO3. In a word, whether all the sulphates do really enter into lhe simple series I have above given. If, as I contend, the molecule of alum contains but 1 SO3, this molecule will be capable of combining with 1, 2, 3, 4 . . . . Aq, I that is to say, that alum, if we quadruple its formula so as to rransform it in S'Ol6al6K2, should be able only to combine I with 4, 8, 12, 16 Aq,—whilst if the real molecule of ! lum contains 4 SO3, it should be able to combine with 1, 2, 3, 4, j), Aq. We learn from experiment that the octohedric j Hums (with 4 SO3) contain 24 Aq,—that the ferric hexagonal ‘ Hum contains 12 Aq,—that the ferric alum precipitated by absolute Llcohol retains 8 Aq,—that the sulphateof chrome and soda retains Aq at 100° C,—and lastly that dried common alum retains 4 Aq. If octohedric alum, instead of a multiple of 4, contained for ixample 25 Aq, then, in reducing its formula to 1 SO3, we hould have SO'1 Al^ICi- 4- Aq, which is impossible. (Such not being the case, however, we contend that the nolecule of alum should be represented with 1 SO3, as with that