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Solubility of CO2 increases with increasing pH

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urtula:
Hello all,

I am aware that adding CO2 to water will decrease the pH and the CO2 + H2O <--> H+ + HCO3- <--> 2H+ + CO32-equilibrium.
However, I do not understand why CO2 would have a higher solubility at higher pH.
Would it be too simply to state this is due to Henry's law? If the pH of the water is high, limited amounts of CO2 are in the water and if I then inject air rich in CO2 in the water, a higher solubility of CO2 in the water will be reached because of a lot more CO2 is present in the air, shifting the equilibrium more towards dissolving (higher solubility) CO2 in the water?

Hunter2:
Higher pH means solution is more alcaline. CO2 is in water an acid, which neutralize the higher pH to lower one, what means more CO2 will be dissolved and forming Carbonate.

urtula:

--- Quote from: Hunter2 on June 17, 2023, 10:57:31 AM ---Higher pH means solution is more alcaline. CO2 is in water an acid, which neutralize the higher pH to lower one, what means more CO2 will be dissolved and forming Carbonate.

--- End quote ---
Yeah, that I understand, but is that the same as having a higher solubility?
I get that at a higher pH more CO2 will be able to dissolve in the water (and thus reduce the pH and ultimately increase the concentration of cO2 in the water), however is this the same as having a higher solubility at higher pH?
If this is the case, is it then because the higher the pH, the less CO2 is present so the concentration of CO2 in the water is lower (at high pH) than at low pH (high CO2 concentration) ?

Perhaps I am just struggling with the wording (I am not a native speaker).

Hunter2:
The soloubility is higher at higher pH, because of chemical reaction. Not Opposit.

Borek:

--- Quote from: urtula on June 18, 2023, 11:11:54 AM ---Yeah, that I understand, but is that the same as having a higher solubility?
--- End quote ---

Define "solubility" and we will start from there.

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