Volume 1

Experimental chemistry for junior students / by J. Emerson Reynolds.

  • Emerson Reynolds
Date:
1881-1888
Catalogue details

Licence: Public Domain Mark

Credit: Experimental chemistry for junior students / by J. Emerson Reynolds. Source: Wellcome Collection.

    22/168 page 6
    solid state, and were thus enabled to get within the sphere of each other’s attraction. We thus learn that chemical action is greatly facili- tated by the solution or liquidity of one or all of the bodies engaged. We shall find later on, Experiment 53, that the fine state of division of a solid tends to a similar result. In some of the experiments already cited, the student will have ' observed the evolution of heat and light during chemical action. Thus, when the magnesium wire burned in air, much heat and an intense light were produced. But electricity is also freely developed in certain chemical actions, and in fact the source of electricity in an ordinary galvanic cell is chemical action. Experiment 8.—The simplest form of galvanic cell may be easily made thus:—Take a glass vessel, such as a tumbler (a, fig. 3), and fill it about two-thirds with water, to which one-tenth part of oil of vitriol (sulphuric acid) has been added. Next cut a slip of clean sheet zinc, Zn, a little longer than the glass; its width may be equal to half the diameter of the vessel. Make a hole through one end of the slip, pass a piece of bright copper wire through it and fasten securely by twisting the wire. Prepare Fig. 3.
    digitised image 1
    digitised image 2
    digitised image 3