[free kg solvent]

What's the difference between "free kg" and "kg" of H2O (in the basis pane of REACT)?

 

Thanks!

[Eh-Ph diagram for Antimony]

Thank you, Brian. The thermo_minteq.dat has all the Sb species and minerals I need, but when I try to use it in an Eh-pH diagram, I get a warning "Reaction for H2(g) is missing; can not plot water limit". Do I need to add H2(g) to the database? I would have thought it would have that already? Sorry for these beginner questions and thanks for your help!

[Eh-Ph diagram for Antimony]

Hello,

 

I'm sorry; I have the feeling this is going to be a very basic question. I am trying to make an Eh-pH diagram for Sb using Act2, but I don't see a antimony in the diagram species. Please help.

 

Thank you!

[estimate uncertainty on saturation indices]

Hello,

 

I am using spec8 to determine saturation indices with respect to a number of different minerals in a system that I am working on. I would like to add error bars on the plot I am making with the indices. Do you have any suggestions on how to estimate the uncertainty associated with the saturation indices calculations? Thanks for your help!

[can't plot scatter data]

Thank you! Fixed it and now it works!

[can't plot scatter data]

Hi Tam,

 

You'll want to take a look at the Scatter Data Appendix in the Reference Manual, which you can get to by clicking on the Help tab in Act2. Make sure your two columns are spelled correctly - Mn++ and Eh, and that for Mn++ the data is entered as log activity. Could you post a script for your Act2 diagram and text file so we can try to troubleshoot this? Btw, which version of GWB are you using? 8.0 uses the Geochemist's Spreadsheet which makes adding scatter data really simple, although a text editor like notepad works just fine.

 

Brian Farrell

 

 

Thank you,

 

Attached is my scatter file. Thanks again!

Mn scatter file eh Mn M.txt

[can't plot scatter data]

Hello,

 

I am trying to make a plot in Act2 that has Mn activity on the y-axis and eh on the x-axis. The system is at a constant pH 7 and H2O activity is equal to 1. It appears I was able to do this successfully. Now, I would like to plot field data of eh and Mn activity for a number of samples. I have made the text file but when I tried to "get scatter data", I received the error message:

 

Can't plot scatter data; doesn't contain: H2O

 

Thank you for your help!!!!!