The usual effect of increasing the
strength of the liquid upon the volta-electromotive force was to
considerably increase it, but its effect upon the thermo-electro-motive
force was to largely decrease it. The degree of potential of a metal
and liquid thermo-couple was not always exactly the same at the same
temperature during a rise as during a fall of temperature; this is
analogous to the variations of melting and solidifying points of
bodies under such conditions, and also to that of supersaturation of a
liquid by a salt, and is probably due to some hinderance to change of
molecular movement.
The rate of ordinary chemical corrosion of each metal varied in every
different liquid; in each solution also it differed with every
different metal. The most chemically positive metals were usually the
most quickly corroded, and the corrosion of each metal was usually the
fastest with the most acid solutions. The rate of corrosion at any
given temperature was dependent both upon the nature of the metal and
upon that of the liquid, and was limited by the most feebly active of
the two, usually the electrolyte.
Pages:
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111