الفهرس 
Temporary ion association in an electrolyte solutionOnly 14 pages are availabe for public view
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Abstract
Debye – Hückel model assumed that the ions were almost in random thermal positions. The slight deviation from randomness rises to an ionic cloud around a given ion a positive ion of charge z+eo being surrounded by a cloud of excess negative charge z-eo The thermal motions effectively prevent any complete ordering, but the final situation is a dynamic compromise between the electrostatic interactions tending to produce ordered configurations and the kinetic collisions tending to destroy them. The problem is to calculate the average electric potential of a given ion in the solution due to all the other ions. Bjerrum suggested that a pair of oppositely charged ions may be trapped in each other’s columbic field (i.e. ion-pair may be formed) due to thermal energy would be not sufficient for ions to continue their independent movement in the solution. The ions of the pair together form an ionic dipole on which the net charge is zero.The probability of finding an ion of one type charge near an ion of the opposite charge varies in an interesting way with distance (Figure2). For small values of r, the function Pr is dominated by eλ/r rather than by r2, and Pr increases with decreasing r, for large values of r, eλ/r = 1 and Pr increases with increasing r because the volume (4 π r2 dr of the spherical shell increases as r2.