Titration problem, please help!

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cn0702
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Titration problem, please help!

Post by cn0702 »

100ml of a 0.10M NH3 solution is titrated with a 0.05M HCl solution.
pKb for NH3 is 4.75

What is the pH of the NH3 solution before adding HCl?

pKb=-log Kb
Kb=1.778x10^-5

What is the pH after 100ml of HCl is added?

What is the pH after an additional 100ml is added (total HCl v=200ml)?

I'm not sure why I can't seem to get the correct answers for the pH of this buffer solution.

Please help me w/ detailed steps!

Thank you!
expert
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Joined: Sun Feb 22, 2009 8:08 pm

Post by expert »

Look at some examples of similat tasks. It may help to solve your problem. Keep in mind that NH4OH is a weak base and not fully dissociated while HCl is a strong acid and it is fully dissociated.
http://answers.yahoo.com/question/index ... 150AA07bFX
http://www.scribd.com/doc/19348945/Solu ... r-solution
http://www.ask.com/questions-about/Nh4cl-And-Ph
Remember safety first! Check MSDS and consult with professionals before performing risky experiments.
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