Calculating K when there is multiple phases

[Phuong Tran 1G]

What do you do when the equilibrium equation includes both aqueous and gas phases? Do you solve for each independently and somehow add them or do you convert?

[Alice Ma 2K]

You would have to convert the gaseous species into concentration using the Ideal Gas Law and find K_c. There is no way to find K_p because the aqueous species have no partial pressure.

[Andrew Liang 1I]

I think in that case we would need to convert the gas to molar concentration using the equation: concentration= P/RT.

[kim 2I]

When calculating K, all the components should be in the same "form/units." Therefore, the concentration of the gas would have to be calculated using the Ideal Gas Law of PV=nRT (divide by V on both sides, moles (n) over V = concentration, therefore, conc=P/RT). Finally the Kc can be calculated: Kc=[products]/[reactants].

[Amy Xiao 1I]

Thank you for clarifying why aqueous solutions cannot have partial pressure; I was under the impression that you could convert either to partial pressure or concentration for each of them.