18)
The SI unit of conductance is siemens, represented by the symbol
‘S’ and is equal to ohm–1 (also known as mho) or W–1 The inverse of
resistivity, called conductivity (specific conductance) is represented by
the symbol, k (Greek, kappa) IUPAC has recommended the use of term
conductivity over specific conductance and hence we shall use the term
conductivity in the rest of the book The SI units of conductivity are
S m–1 but quite often, k is expressed in S cm–1