The Use of the Rotating Anode and Mercury Cathode in Electro-Analysis.

Abstract

The deposit of metal was in each instance beautiful, light gray in color, metallic, and perfectly adherent. The arsenic existed in the solution as a sulpharsenate = (0.2000 gram of arsenic). Universityof Pennsylvania.[Contribution from the John Harrison Laboratory of Chemistry, No. 99.] THE USE OF THE ROTATING ANODE AND MERCURY CATHODE IN ELECTRO-ANALYSIS.

The Mercury Cathode and its Applications.

“…Loss of weight due to the formation of a fine suspension of mercury has also been reported (19). This acid has, however, been used successfully in certain procedures (1,12,13,80,101,155).…”

“…The single cup has been used to separate iron from cerium (24,168) and the rare earths as a group (13,80,116).…”

“…Cadmium has been deposited quantitatively from a solution of its sulfate (12,80,125,155) and the method has been used to determine the atomic weight of cadmium using bromide and chloride solutions, as well as the sulfate (7, 8, 10, 69, 86, 126, 134a). It is also deposited in the presence of nitric acid (12), and the latter acid is the best medium for mercury (1, 80,155). Bóttger found that the use of a nickel or cobalt amalgam prevented the formation of mercurous chloride when mercury was deposited from a solution of mercuric chloride (18).…”

“…Group IVA (C, Si, Ge, Sn, Pb): Germanium and tin are both quantitatively deposited in mercury. Kollock and Smith determined tin by deposition from sulfuric acid solution (80) but hydrochloric acid solution is reportedly more satisfactory (119). Although lead is quantitatively separated, some of it is partially deposited on the anode and suggestions for minimizing the anodic deposit include use of an alkaline solution (166), the rigid mercury cathode (19) deposition as an amalgam on a platinum dish (1, 155).…”

“…A further contribution made by Smith and his students was the investigation and adoption of the rotating anode in place of the stationary type (79, 80), although doubts concerning its advantages were raised by others who favored simplicity and economy in the apparatus (13,27,158). Common ground for the two opposing views was provided by Frary, who devised magnetic methods for 2 There is some confusion in the literature regarding Gibbs' later papers on this subject.…”