what is liquid junctionpoint and liquid junction potential plzexplain with figure if possible.

When two solutions of different concentrations are in contact with each other, the more concentrated solution will have a tendency to diffuse into the comparatively less concentrated solution. At the point of the junction, there develops a potential difference because of the ionic transfer between the solutions. This potential is known as the liquid junction potential.

This liquid junction potential can be calculated as follows,
In the case of two solutions of different concentrations of HCl,
  Electromotive force(EMF) without transference,
        E1 = RT/F x ln(a2/a1)
where a2 and a1 being the activities of HCl in the two solutions, R being the universal gas constant, T being the temperature and F being the Faraday's constant
  ​EMF with transference,
        E2 = tMRT/F x ln(a2/a1)
where tM being transport number of Cl-

Liquid junction potential = E2 - E1 = (tM - 1) RT/F x ln a2/a1.


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