rnelsonchem / phcalc Goto Github PK

Can you provide example calculations for Na2SO4/Sulfuric acid in the documentation?

The software keeps bringing up errors for numpy and i would assume the other import functions. Since it seems like the tinspire cx 2 cas is unable to use the import function, is there another way to have it be run? @rnelsonchem

In the carbonic acid example of the README, the pKa values of H2CO3 are given as [3.6, 10.32] and the pH of 0.01 M is computed to be 2.834.

According to this list the pKa values should be [6.35, 10.33].
Using these values gives a pH of 4.176 which is consistent with the value of 4.18 for 10 mM given here.

Is it just a typo?

Since pKa will vary with both the concentration of a species, as well as the temperature of the solution, I think it will be worthwhile to introduce a method to calculate a more precise pKa value for a species given one or more constants defining the relationship between a species' dissociation constant and temperature and concentration.

I will hopefully find some time to implement and create a PR in the next week or two.

Hey Ryan, I am using a slightly rewritten version of your pHcalc in my RTM framework and planning to add the framework as a chapter of my PhD thesis or supplemental information. Thus, I was wondering how should I cite your work? do you have a reference or DOI? At the moment I have only your name and link to the GitHub repository. Looking forward to your reply.

RTM framework:
https://github.com/biogeochemistry/PorousMediaLab

Looking for feedback on new object class names. Here's the proposed nomenclature:

• AcidAq -- Used to define aqueous species that have known Ka/pKa values
• IonAq -- Used to define an aqueous ion. These are assumed to not participate in any aqueous equilibria, but their charge will affect the overall charge balance
• SystemAirEquilibrated -- A subclass of System to equilibrate the solution with atmospheric CO2. See PR-6
• AcidGas -- Used to define a gas in equilibrium with the solution. In solution, the gas participates in acid/base equilibria. I.e. NH3 and CO2/H2CO3. See PR-7

Hi,

I would like to use your “pH Calc” algorithm in my Reactive-Transport-Toolbox.

This reaction toolbox solves advection-diffusion-reaction PDE for saturated (at the moment) and not saturated (will be added soon) flow.
The problem that I encounter at the moment that I solve the pH for vectors and I am iterating across indexes of concentrations. In this implementation of pHcalc it takes very long time to solve for each time step in PDE. Thus, I was wondering if it is possible to accelerate the estimation of pH in your toolbox? One of the solution would be to provide a jacobian. Would it be possible to make?

Thanks.

Looking forward to your reply.

My toolbox is here:
https://github.com/biogeochemistry/PorousMediaLab

Should it be caoh2 = Acid(pKa=(14-pkb[Ca(OH)2]), charge=+2, conc=0.01) ?