- #1
Bipolarity
- 776
- 2
So suppose you have ammonia gas suspended above a column of water. Because both ammonia and water are polar, some of the ammonia will immediately dissolve into the water, forming a solubility equilibrium.
[tex] NH_{3}(g) \rightleftharpoons NH_{3}(aq) [/tex]
Henry's Law states that:
[tex] S_{g}=kP_{g}[/tex]
However, if I use the equilibrium constant expression, I get:
[tex] K_{sp} = \frac{RT[NH_{3}(aq)]}{P_{NH_{3}(g)}} [/tex]
According to this expression, if I increase the pressure by a factor of λ (or decrease the volume by λ), then Q will decrease by λ, so equilibrium will shift to favor the production of aqueous ammonia, however I am not so sure that this will be proportionate to the pressure increase. I see a necessary contradiction between Henry's Law and Le Châtelier's Principle.
OF course I have probably made some type of mistake, but I can't find it... I would appreciate any help.
THanks!
BiP
[tex] NH_{3}(g) \rightleftharpoons NH_{3}(aq) [/tex]
Henry's Law states that:
[tex] S_{g}=kP_{g}[/tex]
However, if I use the equilibrium constant expression, I get:
[tex] K_{sp} = \frac{RT[NH_{3}(aq)]}{P_{NH_{3}(g)}} [/tex]
According to this expression, if I increase the pressure by a factor of λ (or decrease the volume by λ), then Q will decrease by λ, so equilibrium will shift to favor the production of aqueous ammonia, however I am not so sure that this will be proportionate to the pressure increase. I see a necessary contradiction between Henry's Law and Le Châtelier's Principle.
OF course I have probably made some type of mistake, but I can't find it... I would appreciate any help.
THanks!
BiP