Question
Question: What will be the pH at the equivalence point during the titration of a 100 mL 0.2 M solution of CH3C...
What will be the pH at the equivalence point during the titration of a 100 mL 0.2 M solution of CH3COONa with 0.2 M solution of HCl ? Ka = 2 × 10–5.
A
3 – log2
B
3 + log2
C
3 – log 2
D
3 + log 2
Answer
3 – log2
Explanation
Solution
CH3COONa + HCI ⟶ NaCI + CH3COOH
t=0 20 m eq. 20 meq. teq.
– – 20 meq.
[CH3COOH] = 20020 = 0.1 M
pH = 21 [pKa – log C] = 21 [5 – log2 + 1]
= 21 [6 – log2] = 3 – log 2