Menu

Discussion Forum

New Discussion
Filter

Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

Define PH

Posted May 18, 2012, 2:38 p.m. EDT Low-Frequency Electromagnetics, Materials, Modeling Tools & Definitions, Parameters, Variables, & Functions Version 4.2, Version 4.2a 2 Replies

Bahar
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam


Hi

Anyone has any idea how I can define PH of my solution in ACDC module?

Best
Bahar
2 Replies Last Post May 22, 2012, 11:52 a.m. EDT
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago May 18, 2012, 4:02 p.m. EDT
Hi

Interesting question, my first reply would be to take the concentration of H+ from the charge and call that the H+ activity (not strictly true but at least it is a first guess) and then take the log10 of the H+ activity to get the PH, and the units of pH are log(L/mol) Wiki found it back for me, hope its' right, mostly yes, but one never knows ;).

Some adjustments of the type of medium/solution and its composition must be used too (as the charge is for me the number of e- which is not necesarily the corresponding number of free H+)

Now, I must admit I havent done any serious chemistry for years, so this would need some serious and mandatory validation, as well as probably some corrections ;)

When checking quickly on Wiki it reminds me about the differential measurements used, by using electrodes potential measurements and calibration of these with known chemicals

But COMSOL has some excellent chemistry specialists, they should know, not to say all those using COMSOL for chemistry out there.

I'm eager to hear more ...

--
Good luck
Ivar
Hi Interesting question, my first reply would be to take the concentration of H+ from the charge and call that the H+ activity (not strictly true but at least it is a first guess) and then take the log10 of the H+ activity to get the PH, and the units of pH are log(L/mol) Wiki found it back for me, hope its' right, mostly yes, but one never knows ;). Some adjustments of the type of medium/solution and its composition must be used too (as the charge is for me the number of e- which is not necesarily the corresponding number of free H+) Now, I must admit I havent done any serious chemistry for years, so this would need some serious and mandatory validation, as well as probably some corrections ;) When checking quickly on Wiki it reminds me about the differential measurements used, by using electrodes potential measurements and calibration of these with known chemicals But COMSOL has some excellent chemistry specialists, they should know, not to say all those using COMSOL for chemistry out there. I'm eager to hear more ... -- Good luck Ivar
Bahar
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago May 22, 2012, 11:52 a.m. EDT
Thanks for reply Ivar

I'm trying to model the PH by charge concentration since it was the first solution that came to my mind too. Still working on that...
But I also hope some people who are doing chemistry modeling can give us some idea too
Thanks for reply Ivar I'm trying to model the PH by charge concentration since it was the first solution that came to my mind too. Still working on that... But I also hope some people who are doing chemistry modeling can give us some idea too

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.

Suggested Content