A Comprehensive Treatise on Inorganic and Theoretical Chemistry

PL.ATINUM 101
S. Bidwell studied the relation between the resistance, R, and the thermal
expansion ; and A. Stein, the relation between the resistance and the melting-point.
According to E. L. Nichols, if I denotes the length of platinum at temp, up to
near the m.p., then taking the values of R and I at 0°, as unity, the corresponding
values of Z and R are :
I . 1-0000 1-00125 1O0489 1-01022 1-01229 1-01371 1-01495 1-01567
R . l-OOOO 1-5057 2-3035 3-3533 3-7090 3-8904 40655 4-2005
W. Broniewsky studied the subject. The relation between the resistance and the
thermal conductivity was studied by G. Wiedemann and R. Franz, and H. Reddemann
; and W. Jager and H. Diesselhorst observed that platinum has a greater
value for the ratio thermal : electrical conductivity, and a greater temp. coefF.
than corresponds with Wiedemann and Franz's rule—3. 21, 5. F. Streintz, and
8. Bidwell studied the relation between the specific heat and the resistance of
platinum ; and N. F. Mott, the relation between the latent heat, the m.p., and the
electrical conductivity. R. Bornstein said that the conductivity of platinum is
increased by exposure to light ; but C. W. von Siemens observed no perceptible
change. The subject was discussed by C. Hausemann, and F. Weber. According
to W. Jager and H. von Steinwehr, the percentage increase in the resistance, SR,
of a platinum wire—0-1 mm. in diameter, and 35 cms. in length, and total resistance
5 ohms—by the passage of a current of C amperes, as the temp, rises 86°, is as
follows :
(1 . . . 00043 0Ol 96 00355 0-0524 0-0689 O-IOOO
SR . . O 0-035 OIO 0-235 0-41 0-88
80. . . O 0009 0-025 0-059 0101 0-220
The subject was studied by F. Weber. A. Broca and M. Turchini studied the
resistance of platinum to alternating currents. A. T. Waterman, and J. W. Nicholson
.studied the electron theory of conduction. K. Bamberger observed no change in
the resistance of platinum in a magnetic field, and the subject was studied by
W. Kohlrausch, S. U. Christie, and P. Kapitza ; and L. Grmimaeh found that a
transverse magnetic field produces but a very small change in the resistance.
F. Weigert found that a platinum wire 0-05 mm. diameter and of resistance
13-18 ohms, had a resistance of 13-311 ohms in a magnetic field of 11,500 gauss,
and 13-242 ohms in a magnetic field of 16'21O ohms. N. d'Agostino observed
that with a wire 0-15 mm. and 13*48 ohms resistance, the quotients x of the changein
the magnetic field and the total resistance for magnetic fields of 2400, 3690,
4840, and 6510 gauss are respectively — 0-0s25, 0-0561, OC)4Il, and 0-0420.
J. Frenkel and N. Miroluboff, G. Borelius, H. M. Barlow, A. T. Waterman,
F. Simon, H. F. Mott, and E. H. Hall studied the theory of conductivity ; and
Z. A. Epstein, the periodic variation of the resistance of metals with at. wts.
The heating effect of the electric current in platinum was studied by
E. Becquerel,2 G. D. Botto, J. G. Children, H. Davy, A. Farkas and H. H. Rowley,
R. T. Glazebrook and co-workers, W. R. Grove, E. Lenz, J. Muller, W. H. Preece,
P. Riess, A. de la Rive, M. Viard, and F. Zollner ; the use of platinum for
resistance wires in electric furnaces, by G. Nordstrom ; the development of
stationary waves by wires heated by alternating currents, by A. Imhof ; the effect
on sounds produced by the current, by T. Argyropulos, B. M. Ferguson, and
W. H. Preece ; the mechanical action of the current by A. Berliner, E. Edlund,
F. Exner, W. R. Grove, R. Nahrwold, G. -von Quintus-Icilius, and H. Streintz ;
and the resistance at the contact surface of electrode and electrolyte by O. Scarpa ;
and R. Holm, at the contact of two surfaces ; E. Branly observed the unipolar
conductivity of the Ag-Mica—Pt condenser ; F. Skaupy and O. Kantorowicz, the
resistance of the compressed powder ; H. Rohmann, the unipolar contact between
two pieces of platinum wire which have been heated to incandescence for a long
time in vacuo ; R. Holm and R. Stormer, the resistance of platinum contacts ; and