Electrochemical determination of acid-base and oxidation-reduction properties of concentrated phosphoric-acid solutions progressively neutralized by soda

• Main Authors: Bessiere, J., Aroua, M.K.
• Format: Article
• Published: Canadian Journal of Chemistry-Revue Canadienne De Chimie 1992
• Subjects: TA Engineering (General). Civil engineering (General); TP Chemical technology
• Online Access: http://eprints.um.edu.my/7516/; http://www.nrcresearchpress.com/doi/pdfplus/10.1139/v92-229

Acid-base properties in 7 M H3PO4 medium neutralized by soda are characterized with an R(H) acidity function and R(H2PO4-), R(HPO42-), R(PO43-) basicity functions, which respectively represent the H+ activity in these media and their ability to donate H2PO4-, HPO42-, PO43- ions. The acidity level of these media (Na/P = 0.0-1.6), changes from R(H) = -2.7 to R(H) = +7.5. The accessible potential domain for the media studied is close to 1. 23 V. Activities of these solutions in water vary between 0.66 and 0. 8 1. The ranges of electroactivity for platinum, carbon, and mercury electrodes are also determined.