Question

The pka of hypochlorous acid is 7.530. a 52.0 ml solution of 0.149 m sodium hypochlorite (naocl) is titrated with 0.293 m hcl. calculate the ph of the solution

Answer 1

Answer:

The pH of the buffer solution is 7.236

Explanation:

Henderson - Hasselbalch equation of a buffer solution consisting of a weak acid and its conjugate base is given as:

$pH=pK_a+log(\frac{[conjugate base]}{[weak acid]})$

The hypochlorous acid (HCIO),  is the weak acid  and the conjugate base the  hypochlorite anion (ClO⁻) is the conjugate base.

The dissociation of the salt is given by:

NaOCl(aq)  ⇒  Na⁺(aq) + ClO⁻(aq)

The salt dissociate at a ratio of 1:1

Substituting values to get:

$pH=pK_a+log(\frac{[conjugate base]}{[weak acid]})\\pH=7.53+log(\frac{0.149M}{0.293M})\\pH=7.53-0.2937\\pH=7.236$

The pH of the buffer solution is 7.236