Ion association of dilute aqueous sodium hydroxide solutions to 600{degrees}C and 300 MPa by conductance measurements

Journal Article · Thu Aug 01 04:00:00 EDT 1996 · Journal of Solution Chemistry

DOI:https://doi.org/10.1007/BF00973780· OSTI ID:442250

Ho, P C; Palmer, D A ^[1]

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1. Oak Ridge National Lab., TN (United States)

The limiting molar conductances {Lambda}{sub o} and ion association constants of dilute aqueous NaOH solutions (<0.01 mol-kg{sup {minus}1}) were determined by electrical conductance measurements at temperatures from 100 to 600{degrees}C and pressures up to 300 MPa. The limiting molar conductances of NaOH{sub (aq)} were found to increase with increasing temperature up to 300{degrees}C and with decreasing water density p{sub w}. At temperature {ge}400{degrees}C, and densities between 0.6 to 0.8 g-cm{sup {minus}3}, {Lambda}{sub o} is nearly temperature-independent but increases linearly with decreasing density, and then decreases at densities <0.6 g-cm{sup {minus}3}. This phenomenon is largely due to the breakdown of the hydrogen-bonded structure of water. The molal association constants K{sub Am} for NaOh{sub aq} increase with increasing temperature and decreasing density. The logarithm of the molal association constant can be represented as a function of temperature (Kelvin) and the logarithm of the density of water.

• Sponsoring Organization: USDOE
• OSTI ID: 442250
• Journal Information: Journal of Solution Chemistry, Journal Name: Journal of Solution Chemistry Journal Issue: 8 Vol. 25; ISSN JSLCAG; ISSN 0095-9782
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
AQUEOUS SOLUTIONS
HIGH PRESSURE
MEDIUM PRESSURE
PRESSURE DEPENDENCE
SODIUM HYDROXIDES
SOLVATION
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0273-0400 K
TEMPERATURE RANGE 0400-1000 K