11. By calculating the mean activity coefficients from them the theory could be tested against experimental data. 12. The Nernst equation for the distribution of the anion, ignoring the activity coefficients is written. 13. The activity coefficients for silver and chloride are 0.75 and 0.76, respectively. 14. More generally, the mean activity coefficient of a compound of formula A " p" 15. Where " a " is the activity, and the ? are thermodynamic activity coefficients . 16. In this situation the mean activity coefficient is proportional to the square root of the ionic strength. 17. Where activity coefficients are not available, the coefficient may be assumed to be 1.0. 18. A typical group contribution method using group interaction values is the UNIFAC method which estimates activity coefficients . 19. The ^ \ dagger symbol has been used here to dinstinguish between the two kinds of activity coefficients . 20. Single-ion activity coefficients can be calculated theoretically, for example by using the Debye H�ckel equation.
