Conductance of n-alkylammonium and n-alkanolammonium chlorides and picrates in water at 25°C

Precise conductance measurement are reported at 25°C in water for ethanolammonium chloride and picrate [(EtOH)NH₃Pic], propanolammonium picrate [(ProOH)NH₃Pic], butanolammonium picrate [(BuOH)NH₃Pic], pentanolammonium picrate [(PeOH)NH₃Pic], ethylammonium chloride (EtNH₃Pic), n-propylammonium picrate (PrNH₃Pic), n-butylammonium chloride and picrate (BuNH₃Pic), n-pentylammonium chloride (PeNH₃Cl) and n-heptylammonium chloride (HepNH₃Cl). Comparison of the limiting ionic conductance for the straight chain alkylammonium ions with their terminal hydroxyl-substituted analogs reveals that only for the ethanolammonium ion is the limiting ionic conductance significantly higher. In the other cases a much smaller, nearly constant, difference is observed. These results are explained in terms of the effect of the OH group on the interaction between water and the alkyl chain in the ammonium ions.