HEPES, 2-[4-(2-hydroxyethyl)piperazin-1-yl]ethanesulfonic acid, is a diprotic acid often used to create buffers compatible with biological samples....

HEPES, 2-[4-(2-hydroxyethyl)piperazin-1-yl]ethanesulfonic acid, is a diprotic acid often used to

create buffers compatible with biological samples. A 10.0 mL sample of HEPES was titrated with

0.100 M NaOH.

a. To 2 places past the decimal point, determine the values of pKa1 and pKa2 for HEPES

b. Calculate the initial molarity of the HEPES solution to 4 sig figs.

c. A 20.0 mL portion of 0.20 M HEPES is titrated with 0.100 M NaOH. Calculate the pH at the first

and second equivalence points of the titration.

Expert Solution

queen_honey_blossom answered 1 year ago

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