Activity

[DSloane]

Hello,

 

I am trying to create a pourbaix diagram, but am unsure what to write as my activity? This is my first time using this software so any help would be appreciated!

[katezat]

Hello,

 

Act2 works in terms of species’ activity, which is technically unitless, but close to the molal concentration. Remember, the activity is equal to the molal concentration of a species times its activity coefficient. When people construct diagrams by hand they typically assume the activity is equal to the concentration, but if you have a fluid of a certain composition in mind you can use SpecE8 to calculate the activity of the main species.

Hope this helps,

Katelyn

Aqueous Solutions LLC

[Faizanqaiser]

Dear Katelyn

Hi , how are you, can you please explain me who i calculate activity by using SpecE8

[Brian Farrell]

Hello,

 

You can find a quick tutorial on calculating species' concentrations and activities here. For more information, please see section 7, Using SpecE8, in the GWB Essentials Guide. You can access the Guide from the Help menu of any GWB program.

 

Regards,

Brian Farrell

Aqueous Solutions LLC