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Topic: Determining the Kb from the Ka  (Read 115191 times)

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Offline hunter457

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Determining the Kb from the Ka
« on: November 08, 2009, 01:09:10 PM »
Hydrofluoric acid is a weak acid in aqueous solution; Ka is equal to 6.7 x 10-4. Calculate Kb for the fluoride ion F-


I know that Ka x Kb = Kw, but how do I find out what Kw is. Is it the Kw of water? Also, is the Kb for the fluoride ion different than the Kb for the hydrogen ion?

Offline Borek

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Offline hunter457

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Re: Determining the Kb from the Ka
« Reply #2 on: November 08, 2009, 08:21:35 PM »
Thanks.

So,

Kb=Kw/Ka=1.0x10-14/6.7x10-4= 1.5x10-11

So, Kb=1.5x10-11. Is that right?

Offline Borek

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Re: Determining the Kb from the Ka
« Reply #3 on: November 09, 2009, 03:15:31 AM »
Correct.
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