The values of egr;prime; and egr;Prime; have been measured for pure methyl, ethyl,nhyphen;propyl andnhyphen;butyl cyanides at 1.0 Mc/sec, 9.95, 20.8, and 32.0 kMc/sec. The relaxation time and the distribution parameters have been calculated from Colehyphen;Cole plots. The value of dielectric relaxation time increases from methyl tonhyphen;butyl cyanides (3.8, 4.7, 6.2, 7.5times;10mdash;12sec at 30deg;C) but the distribution parameter is decreasing with increasing chain length (0.14, 0.08, 0.02, 0.00, at 30deg;C). This indicates that probably there is rotation of the CN group around the Csngbnd;CN bond. The cyanides are showing that the most probable enthalpies of activation are less than the corresponding free energies so that the most probable entropies of activation are negative. A recordinghyphen;type dielectric measuring bench has been used for the microwave measurements.
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