Untersuchung der Ionengleichgewichte in Tetrahydrofuranlösungen des 2-Naphthonitril-Natriums

Abstract

With the aid of conductometric measurements the ion equilibria inTHF solutions of 2-naphthonitrile sodium were studied. It was established that in the concentration interval of 10⁻⁴–10⁻⁵ mol/l the equilibrium ion pairs—free ions is predominant$(K_d ^{25 \circ } = 5.3 \cdot 10^{ - 8} )$. The ion pairs are contact (average interion distance about 4.1 Å). In the temperature interval of 25 to 40° the heat of dissociation −ΔH=3.1 kcal/mol, whereas between −40 and −70°−ΔH is 1.26 kcal/mol. At higher concentrations (10⁻²–10⁻³ mol/l) triple ion formation is observed.