(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

To prepare 1M phosphate buffer pH7.8. pKa=7.21. How much molar of Na2HPO4 and NaH2PO4 to be added

I have no confidence in my answer... Can anyone pls have a check?

2. Relevant equations

pH=pKa+lg (base/conjugate acid)

3. The attempt at a solution

7.8=7.21 +lg (a/b)

0.59=lg (a/b)

a/b=3.89

a+b=1-----1

a=1-b -----2

(1-b)/b=3.89

b=0.2045 -Na2HPO4

a=0.7955 -NaH2PO4

Is my way of doing it correct? Did i forget to calculate other things that i must?

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# Homework Help: Phosphate buffer calculation

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