A dilute aqueous solution of `KCI `was placed between two electrodes 10 cm apart, across which a potential of 6 volt was applied. How far would the `K^(+)` ion move in 2 hours at `25^(@)C`? Ionic conductance of `K^(+)` ion at infinite dilution at `25^(@)C` is `73.52 ohm^(-1) cm^(2) "mole"^(-1)`?

Answer

`3.29cm`

Explanation

`lambda_(E) =` Ionic mobility `xx 96500`
`lambda_(M) = lambda_(E) xx (v.f.)`
For `k^(+)` ion v.f =1 so
`lambda_(E) = lambda_(M) = 73.52`
Ionic mobility
`=(73.52)/(96500) =(speed)/("potential gradient")`
speed `(mu) = (73.52)/(96500) xx (6)/(10) = 0.00457 cm//sec`
distance `=mu xxt = 0.000457 xx 7200 = 3.29cm`