CO2 and changing pH

[Guelph_Alex]

Hi,

I was wondering if there is a way to input CO2 at varying fugacities in SPEC_E8, and have it adjust for the pH difference. Say I have a solution at pH 7 originally and want to add 1 atm of CO2 to the solution, can it determine what the resultant pH will be and display the saturation indecies with respec tot the changing pH. Thanks

 

Alex

 

I am running version 6.0.5

[Tom Meuzelaar]

Hi,

I was wondering if there is a way to input CO2 at varying fugacities in SPEC_E8, and have it adjust for the pH difference. Say I have a solution at pH 7 originally and want to add 1 atm of CO2 to the solution, can it determine what the resultant pH will be and display the saturation indecies with respec tot the changing pH. Thanks

 

Alex

 

I am running version 6.0.5

 

Hi Alex:

 

If you have GWB Standard, this is more easily accomplished in the React module- simply set the basis as your starting neutral solution, and add a sliding fugacity for CO2(g) in the Reactants pane.

 

To do this in SpecE8, create two separate models. First configure the SpecE8 basis for your pH 7 solution. In the second model, swap CO2(g) in for the H+ basis component, and set it's fugacity to equilibrium with the atmosphere. This will constrain pH according your CO2(g) buffer. Then compare the output files for the first and second model to observe the difference.

 

Best regards,

 

Tom Meuzelaar

RockWare, Inc.