Electrochemical determination of acidity level and dissociation of formic acid-water mixtures as solvent
JESUS SALVADOR JAIME FERRER
Summary or description
The autoprotolysis constant KHS of formic acid/water mixtures as solvent has been calculated from acid-base potentiometric titration curves. A correlation of the acidity scale pKHS of each media vs. that of pure water has been implemented owing to the electrochemical redox function R°(H+) of Strehlow. The results show that formic acid/water mixtures are much more dissociated than pure water; they are sufficiently dissociated media to allow electrochemical measures without addition of an electrolyte. It has also been shown that for a same H+ concentration the activity of protons increases when formic acid concentration grows. For more than 80% by weight of formic acid the acidity is sufficiently increased so that the whole acidity scale pKHS is in the super acid medium of the generalized acidity scale pHH2O.
Repositorio Institucional CIATEC