Httckel Equation

The value of m may be obtained from the solubility of the salt at the specified temperature and T can be derived from the Debye-Httckel equation, if the solution is sufficiently dilute. For more concentrated solutions, 7 may be estimated by extrapolation from activity coefficients determined in more dilute solution, or by comparison with that of a similar salt at the same concentration. 

The ionic strength (/) of the medium whose pH is to be measured affects the and hence the pH. The Debye-Httckel equation deHnes the activity coefficient y of a Z-valent ion by [62]... 

Httckel has suggested a further modification of the Debve-Huckel equation which takes the form... 

P.Debye and E. Httckel offered an approximate solution of the above equation for the system consisting of weakly charged spherical particles of radius r, when ze% / k T< 1, and sinh (zePoisson-Boltzmann equation, written in spherical coordinates, in this case appears as ... 

Apply the extended Httckel method to H2. Use K = 1.75 use the expression (13.60) of 5 as a function of R plot the valence-electron energy as a function of R compare the predicted value of R with the experimental value. (To avoid solving a secular equation, use symmetry orbitals.) Use 1.0 as the orbital exponent. 

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