Electrochemical determination of acidity level and dissociation of formic acid-water mixtures as solvent

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 Strehlo...

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Detalhes bibliográficos
Autor: JESUS SALVADOR JAIME FERRER
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2012
País:México
Recursos:Centro de Innovación Aplicada en Tecnologías Competitivas
Repositorio:Repositorio Institucional de CIATEC
Idioma:inglés
OAI Identifier:oai:ciatec.repositorioinstitucional.mx:1019/195
Acesso em linha:http://ciatec.repositorioinstitucional.mx/jspui/handle/1019/195
Access Level:acceso abierto
Palavra-chave:info:eu-repo/classification/LEMD/Electroquímica
info:eu-repo/classification/LEMD/Química física
info:eu-repo/classification/cti/2
info:eu-repo/classification/cti/23
info:eu-repo/classification/cti/2307
info:eu-repo/classification/cti/221005
Descrição
Resumo: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.