Statistical Thermodynamic Model for Surface Tension of Aqueous Organic Acids with Consideration of Partial Dissociation

Hallie C. Boyer, Cari S. Dutcher

Research output: Contribution to journalArticlepeer-review

15 Scopus citations


With statistical mechanics, an isotherm-based surface tension model for single solute aqueous solutions was derived previously (Wexler et al. J. Phys. Chem. Lett. 2013) for the entire concentration range, from infinite dilution to pure liquid solute, as a function of solute activity. In recent work (Boyer et al. J. Phys. Chem. Lett. 2015), empirical model parameters were reduced through physicochemical interpretations of both electrolyte and organic solutes, enabling surface tension predictions for systems where there is little or no data. The prior binary model is extended in the current work for the first time to treat multicomponent systems to predict surface tensions of partially dissociating organic acids (acetic, butyric, citric, formic, glutaric, maleic, malic, malonic, oxalic, propionic, and succinic acids). These organic acids are especially applicable to the study of atmospheric aqueous aerosols, due to their abundance in the atmosphere. In the model developed here, surface tension depends explicitly on activities of both the neutral organic and deprotonated components of the acid. The relative concentrations of the nondissociated and dissociated mole fractions are found using known dissociation constants. Model parameters strongly depend on molecular size, number of functional groups, O:C ratio, and number of carbons. For all organic acids in this study, fully predictive modeling of surface tensions is demonstrated.

Original languageEnglish (US)
Pages (from-to)4368-4375
Number of pages8
JournalJournal of Physical Chemistry A
Issue number25
StatePublished - Jun 30 2016

Bibliographical note

Funding Information:
H.B. was supported through a National Science Foundation Graduate Research Fellowship. Part of this work was carried out in the College of Science and Engineering Characterization Facility, University of Minnesota, which has received capital equipment funding from the NSF through the UMN MRSEC under Award DMR-1420013. This material is based upon work supported by the National Science Foundation under Grant No. 1554936.

Publisher Copyright:
© 2016 American Chemical Society.

Copyright 2016 Elsevier B.V., All rights reserved.

How much support was provided by MRSEC?

  • Shared

PubMed: MeSH publication types

  • Journal Article


Dive into the research topics of 'Statistical Thermodynamic Model for Surface Tension of Aqueous Organic Acids with Consideration of Partial Dissociation'. Together they form a unique fingerprint.

Cite this