## stoichiometric mean molal (practical activity coefficient)

in electrochemistry
https://doi.org/10.1351/goldbook.S06024
The practical activity @[email protected] of electrolyte B is given by $\gamma _{\pm }=\frac{a_{\pm }}{\sqrt{\nu _{\text{+}}^{\nu _{\text{+}}}\ \nu _{\text{-}}^{\nu _{\text{-}}}}\ \frac{m_{\text{B}}}{m^{\text{+}}}}$ where $$a_{\pm }$$ is the mean activity of B in solution, $$m_{\text{B}}$$ is the @[email protected] of B, $$m^{\text{+}} = 1\ \text{mol kg}^{-1}$$, $$\nu _{\text{+}}$$ is the number of cations and $$\nu _{\unicode{x2013}}$$ the number of anions in the chosen group B which is taken as the electrolyte. $\nu = \nu _{\text{+}}+\nu _{\text{-}}$
Source:
PAC, 1974, 37, 499. (Electrochemical nomenclature) on page 510 [Terms] [Paper]