Question chemistry

[Ferdowsi]

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What is the ratio of concentration of NaH2PO4- and Na2HPO4- in phosphate buffer at pH 7.4?

Thanks

 

[Ferdowsi]

Anyone???🙁

 

[Danny289]

use Henderson-Hasselbalch equation.

pH=pKa + log (Base/acid)
you have to use pKa 7.21(pka1=2.12, pKa2=7.21, pKa3=12.32) because it is closed to your pH.

7.40= 7.21+ log(HPO4-2/H2PO4-)

log(HPO4-2/H2PO4-)=0.19

(HPO4-2/H2PO4-)=10^0.19
= 1.5
don't worry about this kind of questions my persian firend. 😉
good luck