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Topic: What is the pH of this solution?  (Read 3052 times)

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Offline Joniaguis

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What is the pH of this solution?
« on: January 14, 2009, 07:25:22 PM »
0.202g of the sodium salt of aspirin (C9H8O4) is dissolved in 100ml of water.

Ka of aspirin is 3.162x10-4

Offline AWK

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Re: What is the pH of this solution?
« Reply #1 on: January 15, 2009, 01:49:17 AM »
Thi is a problem of salt hydrolysis
AWK

Offline Joniaguis

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Re: What is the pH of this solution?
« Reply #2 on: January 15, 2009, 05:02:56 AM »
Is this answer right?

Kb= [HA][OH-] / [A-]

[OH-]2 = Kb x [A-]

[OH-] = 5.6237x10-7

pOH= 6.25
Therefore pH is equal to 7.75

Offline Borek

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Re: What is the pH of this solution?
« Reply #3 on: January 15, 2009, 06:14:58 AM »
Looks OK.
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