A Comprehensive Treatise on Inorganic and Theoretical Chemistry

112 INORGANIC AND THEORETICAL CHEMISTRY
J. G. MacGregor, H. Draper, E. Lenz, S. Glasstone and G. D. Reynolds*
J. C. Poggendorff, and C. Fromme. With currents of feeble intensity, the polarization
on the cathode decreases with time, and increases on the anode ; "with more
intense currents, the polarization at the anode soon attains a constant value.
The subject was studied by W. Beetz, A. Bernstein, E. Edlund, F. Forster,
C. Fredenhagen, J. B. Henderson, K. R. Klein, M. Krieg, D. Macaluso, A. Naccari
and G. Guglielmo, J. Parnell, W. Peddie, F. M. Raoult, J. Shields, and F. Streintz.
According to H. Draper, the polarization increases about 1 per cent, for a rise of
temperature of 4°. The subject was investigated by T. R. Robinson, R. Abegg,
F. Exner, A. Bartoli, A. de la Rive, W. Beetz, J. C. Poggendorff, and F. M. Raoult.
R. Tholdte found that the polarization decreases as the size of the electrodes is reduced
until it attains a constant value. The subject was studied by A. Bartoli, E. Lenz,
W. Andauer, and C. Fromme. The effect of the concentration of the electrolyte was
examined by E. Bouty, C. Fromme, and J. M. Gaugain ; and the rate of the reaction
with hydrogen on the cathode, by L. P. Uammett. E. Lenz observed that with the
same current density, the polarization decreased with increasing cone, of sulphuric
acid ; and A. Bartoli, that the addition of glycerol lessened the polarization.
The nature of the surface of the electrodes was found by J. C. Poggendorff to be
such that with smooth platinum electrodes, the maximum polarization was 2-12
to 2*33 volts, and with platinized platinum, 1*83 to 1-85 volts. The subject was
studied by C. Fromme, J. Roszkowsky, E. E. Zimmerman, J. Tafel, E. Brunner,
and A. Friessner. H. J. T. Ellingham discussed the behaviour of nitric acid at a
platinum cathode.
C. F. Schonbein noted that in the electrolysis of water with an anode of smooth
platinum and a cathode of platinized platinum gas is developed less vigorously
than when the electrodes are reversed. R. Luther noted that with ozone, the oxidation
potential with plain electrodes is larger than it is with platinized electrodes.
The subject was discussed by F. Forster, and F. Forster and E. Muller. The
comparison of the two electrodes in the electrolysis of alkali chloride soln. was
made by F. Haber, H. Wohlwill, R. Lorenz and H. Wehrlin, F. Forster and
E. Muller, E. Muller, F. Winteler, W. Oechsli, and A. Biiltemann ; the electrooxidation
of ammonium sulphate was studied by A. Biiltemann ; the reduction of
formaldehyde alkaline soln., by A. Bringhenti ; the electrolysis of formic acid, by
T. Salzer ; the electro-oxidation of potassium ferrocyanide, by A. Brochet and
J. Petit.
According to K. R. Koch, 12 the anodic polarization of a platinum electrode in
acidulated water by oxygen with an electric current insufficient to produce any
perceptible decomposition, is greater than the polarization of the other electrode
by hydrogen. E. Cohn observed that the resistance of a voltameter with large
platinum plates in dil. acid is scarcely affected by polarization. E. I. Spitalsky and
V. V. Pitcheta said that the potential at platinum anodes during the passage of a
current depends on the formation of a film of mol. oxygen, or suboxide. When
the current is broken, the potential depends on the accumulation of at. oxygen.
The behaviour of an anode depends on its previous history, and reproducible results
can be obtained only under strictly uniform conditions. The subject was discussed
by L. Arons, A. Bartoli, W. Beetz, M. Ie Blanc, E. du Bois-Reymond, F. P. Bowden,
J. A. V. Butler and G. Armstrong, J. Daniel, H. Dufour, F. Exner, C Fromme,
W. L. Hildburgh, T. P. Hoar, H. Luggin, D. Macaluso, C. Matteucci, G. Meissner,
T. A. L. du Moncel, J. L. R. Morgan and co-workers, E. Muller, E. Muller and
F. Spitzer, W. Nernst and A. M. Scott, K. Ochs, N. Piltschikoff, J. C. Poggendorff,
A. de la Rive, V. Rothmund and A. Lessing, E. I. Spitalsky and V. V. Pitcheta,
F. Strientz, J. Tafel and B. Emmert, and P. S. Tutundzic. A. V. Pamfiloff studied
the anodic polarization with platinum and with platinized platinum electrodes,
in the form of a loop of wire, in N- and 05.ZV-H2SO4 with current densities O-Ol
to O* 12 amp. per sq. cm. It was found that -with the platinum anode, rotating
at 3OO to 500 revs, per min., the electrode potential rises quickly in the first 5 mins.,