This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1895 edition. Excerpt: ...zinc, copper, paper, zinc... on this supposition. If a piece of zinc connected with one pole of an electrometer be put in contact with a piece of copper connected with the other, a difference of potential is certainly observed, and this may amount to about 0'8 volt. It must be remembered, however, that ...
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This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1895 edition. Excerpt: ...zinc, copper, paper, zinc... on this supposition. If a piece of zinc connected with one pole of an electrometer be put in contact with a piece of copper connected with the other, a difference of potential is certainly observed, and this may amount to about 0'8 volt. It must be remembered, however, that the apparatus is in contact with air, which may exert an oxidising action, and experiments conducted in absence of air, or in artificial atmospheres of other gases, have led to no definite results, probably owing to the difficulty of getting rid of the last traces of air. An indirect method of measurement, used by J ahnl, avoids this difficulty. Peltier found that when a current of electricity was passed across the junction between two metals, a reversible evolution or absorption of heat occurred. By the principles of thermodynamics it follows that an electromotive force must reside there, and by measuring the strength of the current and the total thermal evolution its value can be calculated. J ahn's results shewed that it was always small, a11d rarely amounted to more than a few thousandths of a volt. This appears to disprove the existence of any difference of potential of the order of 0'8 volt, and, though some doubt has been thrown on the validity of the reasoning, it is improbable that the great electromotive force observed by the other method could be so nearly balanced as to disappear in the Peltier effect. Faraday's work led many people to believe that the true seat of the difference in potential, like the source of the energy of the current, was to be found at the junction between metal and liquid, and this appears to be the more probable view. This again is a difficult thing to observe, for, in order to get the...
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Add this copy of Solution and Electrolysis to cart. $22.00, good condition, Sold by Sequitur Books rated 5.0 out of 5 stars, ships from Boonsboro, MD, UNITED STATES, published 1895 by Cambridge, Massachusetts: The Un.
Add this copy of Solution and Electrolysis to cart. $46.00, very good condition, Sold by T A Borden Books rated 4.0 out of 5 stars, ships from Olney, MD, UNITED STATES, published 1895 by Cambridge Univ. Press.
