(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem is need to prepare 400.0 mL of a .200M buffer having a pH of 7.69

Given .5 M of dihydrogen Phosphate at pKa of 6.82

2. Equation to work from is Henderson-Hasselbalch pH=pKa-log of (A-)/(HA)

where (A-) is weak acid and (HA) is the conjugate base

3. I know 400mL is .4 x .2 will give .08 the total for the buffer amount and that (A-) and (HA) will equal that, or x+y= 0.08 so can say x (the weak acid) = 0.08-y

I also know 10 to the (pH-pKa) is 10 to .087 or 7.413

So 7.413=(0.08-y)/y

I need to know how to solve for y and where do I go from there and then how to set up and solve for an ICE table.

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# Homework Help: How to solve buffer calculations-Biochemistry

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