The uses of electrolysis in quantitative chemical analysis / by J. Wilkie.

  • Wilkie, J.
Date:
1890
Catalogue details

Licence: Public Domain Mark

Credit: The uses of electrolysis in quantitative chemical analysis / by J. Wilkie. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    Noe's Thermopyle has been preferred to Clumond's from its readiness, constancy and duration; being inferior to it how- ever for technical purposes. It likewise consists of Zinc- Antimony conples with Iron connections. Neither of these instruments however is as convenient as an ordinary battery, and once damaged very difficult of repair. Meidinger's Hydro-electric battery is recommended by Luckow. There are two metals, Copper and Zinc; and two fluids containing Sulphates of Magnesium and Copper in solution. The battery becomes constant at the and of three weeks de- livering then a current of 3 cc Knallgas per minute, at com- mencing it yields a current af .5 cc Knallgas per minute; in a few days the current reaches a strength of 1.5 cc and 2.5 cc Knallgas. Bunsen's Battery was employed by Lecoq de Boisbaudran, in the preparation of the new metal Gallium by Electrolysis. It was recommended for use by Riche for the estimation of Manganese, one or two cells, one cell if only a small amount of the element was present. Beilstein and Jawein used four cells for the separation of Zinc. It consists of a carbon pole immersed in strong nitric acid contained in an inner porous cell, and a plate of amalgamated Zinc of cylindrical form in dilute sulphuric acid in an outer vessel. Ordinarily a Bunsen's Battery will be found as convenient as any; thongh it must of course be placed in a draught- cupboard. The gases evolved corrode the wires and copper serews very speedily, so that they require frequent cleansing with dilute nitric acid, or rubbing with a file or sand- paper. On once replenishing with acid the current, will con- tinue to flow for 60 hours in quantity sufficient to induce the simpler decompositions. If two cells with carbon plates 8 in by 2 in by 1 in and a Zinc cylinder 8 in high and 4 in diameter be taken about 20 cc of Knallgas are delivered per minute, far more than is required for separation of Copper, and equal to the requirement in the cases of most of the