Kw vs Ka/Kb
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Kw vs Ka/KbIf concentration of H20 is included in Ka of water but not Kw,then why is the concentration of H20 omitted in systems like carbon dioxide/hydrogen carbonate system and Kb?? Why is it that all of this is aqueous system and since H20 is liquid it is not omitted in the Ka of water case? Then why omit concentration of H20(l) in aqueous system for Kc expression? :0
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Re: Kw vs Ka/KbAs water is in huge excess and any amount involved in equilibria is extremely small, so the 'concentration' of water is effectively constant.(Original post by Vadevalor)
If concentration of H20 is included in Ka of water but not Kw,then why is the concentration of H20 omitted in systems like carbon dioxide/hydrogen carbonate system and Kb?? Why is it that all of this is aqueous system and since H20 is liquid it is not omitted in the Ka of water case? Then why omit concentration of H20(l) in aqueous system for Kc expression? :0
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Hence, it can be ignored and a 'new' constant be it ka, kb or kw can be used.
It is only included in kc expressions when it is not the solvent. -
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Re: Kw vs Ka/Kbka of water?(Original post by Vadevalor)
Hmm Why is it included in Ka of water then?
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That's a new one on me!
