Applications of Conductance Measurements

Applications of Conductance Measurements

        1            Determination of the solubility of a sparingly soluble salt.

For a saturated solution of a sparingly soluble salt, the total conductivity of the solution is due to the solvent and the salt. The conductivity of the salt then is .obtained .by subtracting .the conductivity of the solvent from that of the solution, i.e.
Ksalt = Ksoln - Ksolvent
Applying eqn (8) we may write
                                                            (17)
Where   is the conductivity of the salt in the saturated solution and C is the concentration of the solution. For a sparingly soluble salt, its saturated solution may be considered to be to be nearly infinitely dilute. The following approximation may thus be made:-

Hence we may write
                                                                        (18)
Or
                                                                        (19)


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