HELP on ELECTRICAL CONDUCTIVITY, M Siemens/cm (Mega Siemens per centimetre)
The electrical conductivity is the ability of the material to conduct electricity. It is the reciprocal of the resistivity. The electrical conductivity of a metal or electrical conductor depends strongly upon the temperature (see temp. coeff. of resistivity), with the conductivity increasing with decreasing temperature until it reaches a fixed value at cryogenic temperatures. The electrical conductivity depends heavily on the availability of free electrons, for it is the overall movement (drift) of electrons in one particular direction within a metal by the application of an external electric field (or voltage) which constitutes the conduction of an electrical current. Substances without these free electrons are electrically insulating, eg. Sulphur and Phosphorus. Semiconductors such as Silicon, Germanium, Tellurium and Selenium conduct electricity only slightly.
The transition elements of group 11 have the highest conductivities, highest being Gold at 0.63, next Copper at 0.6, followed by Silver at 0.43. The other transition elements have only moderate conductivities, and the lanthanide rare earths very poor conductivities of around 0.01. Semiconductors vary from Tellurium at 2.3x10éï to Silicon at 4x10éç. Yellow sulphur conducts electricity the least at 5x10éçë.
