[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]


Dear David Parkhurst,

In the PHREEQC database there is two equations for CaCO3:

Ca+2 + CO3-2 = CaCO3
        log_k           3.224

        CaCO3 = CO3-2 + Ca+2
        log_k           -8.480

Which one of the equilibrium constants is used by PHREEQC to calculate the
solubility constant?

If both this constants are used doesn't the model became unstable.

Best Regards

Pedro Chambel Leitão
Núcleo Central, Sala 363
2780-920 Oeiras, Portugal
Tel.: +351 21 4239016
Fax:  +351 21 4211272
URL:  http://www.mohid.com

Project Home Page
Complete Water Resources Division Software
USGS Home Page
Water Resources Division Home Page
NRP Home Page
Help Page
USGS Privacy Statement       

Please note that some U.S. Geological Survey (USGS) information accessed through this page may be preliminary in nature and presented prior to final review and approval by the Director of the USGS. This information is provided with the understanding that it is not guaranteed to be correct or complete and conclusions drawn from such information are the sole responsibility of the user.

Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government. 

The URL of this page is: https://wwwbrr.cr.usgs.gov/projects/GWC_coupled/phreeqc/mail/msg00442.html
Last modified: $Date: 2005-09-13 21:04:21 -0600 (Tue, 13 Sep 2005) $
Visitor number 3044 since Jan 22, 1998.