Elements of chemistry : including the recent discoveries and doctrines of the science / by Edward Turner.

  • Turner, Edward, 1798-1837.
Date:
1832
Catalogue details

Licence: Public Domain Mark

Credit: Elements of chemistry : including the recent discoveries and doctrines of the science / by Edward Turner. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    Specific Caloric. Relative Weighu of Moms. Bismuth 0.0288 13.30 Lead 0.0293 12.95 Gold 0.0298 12.43 Platinum 0.0335 11.16 Tin 0.0514 7.35 Silver 0.0557 6.75 Zinc 0.0927 4.03 Tellurium 0.0912 4.03 Copper 0.0949 3.957 Nickel 0.1035 3.69 Iron 0.1100 3.392 Cobalt 0.1498 2.46 Sulphur 0.1880 2.011 From some experiments, the result of which is given in the 10th volume of the Mm. de Cfa et de Ph., MM. Dulong and Petit have inferred that the atoms of simple substances have the same capacity for caloric. Tlie following- table is taken from their essay. (Page 403.) Products of the Weight of each Mom by the coiresponding Capacity. 0.3830 0.3794 0.3704 0.3740 0.3779 0.3759 0.3736 0.3675 0.3755 0.3819 0.3731 0.3685 0.3780* In the new part of his Chemical Philosophy, page 293, Mr. Dalton has made some strictures in reference to this table, tending to show that the opinion of Dulong and Petit cannot be correct, and that it stands in opposition to their own facts. Mr. Dalton argues that the product of the weight of an atom by the coiresponding capacity for caloric, is not a constant quantity; because the capacity of the same substance varies with change of form, or even, according to their own experiments, with variation of temperature, without change of form. To the latter part of the criticism Didong and Petit are certainly exposed; but they have an- ticipated the former by remarking, that the law is not affected by change of form, provided the substances compared are taken in the same state. Whether this position be correct or not, remains to be proved. On Liquefaction. All bodies, hitherto known, are either solid, liquid, or gaseous; and the form they assume depends on the relative intensity of cohesion and re- pulsion. Should the repulsive force be comparatively feeble, the par- ticles will adhere so firmly together, that they cannot move freely upon one another, thus constituting a solid. If cohesion is so far counter- acted by repulsion, that the particles move on each other freely, a li- quid is formed. And should the cohesive attraction be entirely over- come, so that the particles not only move freely on each other, but sepa- rate from one another to an almost indefinite extent, unless restrained by external pressure, an aeriform substance will be produced. Now the property of repulsion is manifestly owing to caloric; and as it is easy within certain limits to increase or diminish the quantity of this principle in any substance, it follows that tlie form of bodies may be * If tlie atomic weights contained in this table were corrected according to the latest determinations, the coincidences between the specific heats of tlie atoms would lie far less striking. See some interesting strictures on this table by Professor A. D. Bache of the University of Pennsylvania, contained in the Journal of the Academy of Natural Sciences of Philadel- phia, for January 1829. B.