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Topic: Buffer solution question.  (Read 1751 times)

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Offline mrorganiclover

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Buffer solution question.
« on: November 17, 2014, 05:49:01 PM »
Good day all.

I'm aware that you're to attempt a question before asking for help here, but I'm really stumped so I need *delete me* I don't want the answer, just the concept/process. I am aware that I have to use the "Henderson-Hasselbalch Equation", just not sure which steps to take.

Starting with a solution that is 0.050M in KH2PO4, calculate the concentration of Na2HPO4 that is required to make a buffer solution of pH 7.80. pKa for H2PO4 - is 7.21

Thanks

Offline Babcock_Hall

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Re: Buffer solution question.
« Reply #1 on: November 17, 2014, 06:56:40 PM »
I would start by writing out the H-H equation and then plugging in what you know.

Offline Borek

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Re: Buffer solution question.
« Reply #2 on: November 18, 2014, 03:13:48 AM »
I would start identifying acid and its conjugate base, then follow Babcock_Hall advice ;)
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