Error:warning: reaction for xxx has a mass imbalance of xxx g/mol

[Cheng]

Dear Jia,

I have figured out the log K problems for TC, but still have problems when given the other ion species. The detail process is in the attachment files, I have closed the precipitation this time, but still struggled here. 

I wish I can get some guide to make it.

Best wishes

Cheng

TC-CaMg.rea thermo-TC_1.tdat

[Jia Wang]

Hello Cheng,

I am glad to hear that you were able to resolve the previous issue with tetracycline. 

The input file you have provided has precipitation disabled. In this case, the program will report the number of phases supersaturated at each step and the name of the mineral most saturated. This is by design and not an error. If you would like to enable precipitation in your reaction, you would need to change the setting under the Config menu. In GWB 12, the option for this is Config --> Iteration. For more information on this mineral precipitation, please see section on 2.3 Initial System in the GWB reaction Modeling User Guide. 

The mass imbalance error in this case is due to the small mass difference between the program's calculation and the mole weight entered for some entries in the dataset. Once I corrected the mole weights for these entries (482.4500 for Ca(TC--) and 483.4500 for Ca(TCH-)+), the mass imbalance warnings were resolved. I believe you would find the TEdit application from the latest GWB version very helpful in checking your customized datasets. The latest version of TEdit reports potential errors at the time of dataset read in. You can access the latest version of TEdit with a paid subscription or a free GWB Community license. Please note that the GWB Community version will only allow you to save your dataset in the latest format, which would not be backwards compatible with GWB 12. 

Hope this helps,
Jia Wang
Aqueous Solutions LLC