ionic conductivity
Defined for ionic species B by \(\lambda = |z_{\text{B}}|\ F\ u_{\text{B}}\) where \(z_{\text{B}}\) is the charge number of the ionic species B, \(F\) is the Faraday constant, and \(u_{\text{B}}\) is the electric mobility of species B. In most current practice \(z_{\text{B}}\) is taken as unity, i.e. ionic conductivity is taken as that of species such as Na+, Ca2+/2, La3+/3 etc. To avoid ambiguity the species considered should be clearly stated, e.g. as \(\lambda (\text{Ca}^{\text{2+}}/2)\).
PAC, 1974, 37, 499. 'Electrochemical nomenclature' on page 512 (