Liquids Conducting Current
Name: Nathan U.
I am reviewing some materials for the electricity unit in
my physics classes. I have come across similar passages in different
texts as follows:
"A conductor in both the solid state and liquid state can carry a current
to complete an electrical circuit. However, a solid conductor involves
the movement of electrons through the atomic lattice, whereas a liquid
conductor transports ionic charges through the solution." (Northwestern
University Materials World Modules, 2002).
I am puzzled by this generalization of liquids. How does liquid mercury
or sodium (nuclear reactor design) conduct electricity? I am not aware of
the requirement of ions.
Whenever you have electrons leaving atoms to travel through the medium, you
have positive ions left behind. With a solid, electrons (usually one per
atom) move through the material and the ions left behind just stay put.
Because the material is solid, the atoms cannot move. In a liquid, the
atoms can move. Of course, they do not move nearly as fast as or in the
same direction as the electrons. Still, they do move.
Dr. Ken Mellendorf
Illinois Central College
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Update: June 2012