[OLD] Database error?

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From: Scott C. Brooks

Subject: Database error?

I believe that there is an error in the thermo database available from LLNL as "thermo.com.V8.R6.full". In this database there is a species listed as:

 

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Co2(OH)3+

charge= 1.0 ion size= 4.0 A mole wt.= 168.8884 g

3 species in reaction

-3.0000 H+ 2.0000 Co++ 3.0000 H2O

500.0000 11.2000 500.0000 500.0000

500.0000 500.0000 500.0000 500.0000

* gflag = 3 [reported logK data used]

* logk source = 76bae/mes

* logk = -11.2000

* logk reference reaction:

* 1.0000 Co2(OH)3+ -3.0000 H2O

* -2.0000 Co++ 3.0000 H+

* calculated g-h-s values:

* delG0f = -180.784 kcal/mol

* delH0f = N/A

* S0PrTr = N/A

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The source of the data is the book The Hydrolysis of Cations by Baes and Mesmer. However in this book, the species is identified as Co2OH+++, Baes and Mesmer do not provide data for Co2(OH)3+. The log K value is correct but the species name, charge, reaction stoichiometry, and mole wt. are obviously incorrect. In the database included with the GWB distribution diskettes is the species Co2(OH)3+ with log K value = 94.

 

From: James W. Johnson

Subject: Re: database error?

The data block for "Co2(OH)3+" in thermo.com.V8.R6.full (and in thermo.com.V8.R6.230) should be replaced by the following corrected data block for Co2OH+++.

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Co2OH+++

charge= 3.0 ion size= 5.0 A mole wt.= 134.8737 g

3 species in reaction

-1.0000 H+ 2.0000 Co++ 1.0000 H2O

500.0000 11.2000 500.0000 500.0000

500.0000 500.0000 500.0000 500.0000

* gflag = 3 [reported logK data used]

* logk source = 76bae/mes

* logk = -11.2000

* logk reference reaction:

* 1.0000 Co2OH+++ -1.0000 H2O

* -2.0000 Co++ 1.0000 H+

* calculated g-h-s values:

* delG0f = -67.408 kcal/mol

* delH0f = N/A

* S0PrTr = N/A

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