Problem: 25.0 mL of 0.2 M sodium formate was titrated with 0.1 M HCl. What is the pH: a) before HCl is added; b) at the half-equivalence point; and c) at the equivalence point? Possible answers, respectively, are given below.A. 8.52; 3.75; 2.46B. 7.52; 4.75; 3.46C. 6.52; 5.75; 5.46D. 5.52; 2.75; 1.46E. 9.52; 6.75; 4.46

FREE Expert Solution

We're being asked to calculate the pH a) before HCl is added; b) at the half-equivalence point; and c) at the equivalence point.

a) before HCl is added

NaHCOO (sodium formate) will break up in the solution:

NaHCOO(aq) → Na+(aq) + HCOO-(aq)

• HCOO- is the conjugate base of HCOOH → HCOO- is a weak base

HCOO- weak baseproton acceptor
H2O → will act as the weak acidproton donor


Equilibrium reaction:        HCOO-(aq) + H2O(l)  HCOOH(aq) + OH-(aq)


Step 1: Construct an ICE chart for the reaction.

View Complete Written Solution
Problem Details

25.0 mL of 0.2 M sodium formate was titrated with 0.1 M HCl. What is the pH: a) before HCl is added; b) at the half-equivalence point; and c) at the equivalence point? Possible answers, respectively, are given below.

A. 8.52; 3.75; 2.46

B. 7.52; 4.75; 3.46

C. 6.52; 5.75; 5.46

D. 5.52; 2.75; 1.46

E. 9.52; 6.75; 4.46

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Weak Base Strong Acid Titrations concept. You can view video lessons to learn Weak Base Strong Acid Titrations. Or if you need more Weak Base Strong Acid Titrations practice, you can also practice Weak Base Strong Acid Titrations practice problems.