Page:Text-book of Electrochemistry.djvu/39

 22 OLDER ELECTROCHEMICAL VIEWS. chap.

Ampere (in 1821) had already assumed that the atoms carry with them a certain invariable quantity of electricity, some carrying a positive charge, others a negative. The charge on the atoms binds an equal quantity of the opposite kind of electricity in the surrounding medium. If a positive and a negative atom collide, the bound electricity in the neighbourhood becomes free, the charges on the two atoms bind each other, and a imion of the atoms takes place with foiination of a neutral compound.

On the other hand, according to Berzelius the atoms are

K Cl

charged polarly, as in the scheme : C^ G^ ' When they

combine, negative electricity from potassium and positive

K ci from chlorine become free, and there is formed (+) Q-

By this process heat and light phenomena were supposed to arise during a reaction. These and similar speculations on the part of Fechner, De la Eive, Schonbein, and Magnus, were too speculative to command attention for any length of time.

Faraday's Law.— Faraday (1),^ in 1834, discovered that every equivalent binds the same quantity of elec- tricity, so that a zinc atom takes up twice as much, and an aluminium atom three times as much, as a hydrogen atom (see p. 7). Berzelius strongly questioned this law, as it was not in agreement with the views which he had previously expressed.

Hittorf's Investigfation. — In the course of the sixth decade of last century, Hittorf (?) performed his work on the migration of the ions, a piece of work of fundamental importance, to which, nevertheless, little attention was paid at the time. We return later to this subject.

Helmholtz's Faraday Lecture (S), — Helmholtz, one delivered the Faraday lecture, in which he discussed the then modern development of Faraday's ideas on electricity. The

^ The italic numbers enclosed in brackets refer to the literature references at the end of the book.

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