Carbonic acid. H_2CO_3, . is a weak acid having a K_a1, =4.5 times 10^-7 and K_a

Question

Carbonic acid. H_2CO_3, . is a weak acid having a K_a1, =4.5 times 10^-7 and K_a2 = 4.7 times 10^-11. A buffer solution is prepared by mixing equal volumes of 0.250 M H_2CO_3 (aq) and 0.500 M NaHCO_3 .Calculate the pH of the buffer solution. 25.0 ml. of a 0.150 M NaOH is required to neutralize a 5.00 mL aliquot of a triprotic acid. H_3A(aq) at its 3^rd equivalence point. The concentration of the acid is: Given the following titration curve answer question A 0.3254 g sample of an unknown diprotic acid is titrated with a 0.1527 M solution of NaOH. Determine the molar mass of this acid

Explanation / Answer

Q7.

H2CO3

this is abuffer so..

H2CO3 <-> H+ + HCO3-

NaHCO3 -> NA+ + HCO3-

there is common ion so this is 1st ionization buffer

pH = pKa1 + log(HCO3-/H2CO3)

pKa = -log(Ka) = -log(4.5*10^-7) = 6.35

so

pH = 6.35 + log(0.50/0.25) = 6.6510

For all further questions, please post multiple questions in multiple set of Q&A. We ar enot allowed to answer to multiple questions in a single Q&A post.

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

---