Question

If a buffer solution is 0.530 0.530 M in a weak acid ( K a = 7.1 × 10 − 6 ) (Ka=7.1×10−6) and 0.150 0.150 M in its conjugate base, what is the pH?

Answer 1

Answer:

pH = 4.6

Explanation:

Given data

• Concentration of the weak acid ([acid]): 0.530 M

• Concentration of the conjugate base ([base]): 0.150 M

• Acid dissociation constant (Ka): 7.1 × 10⁻⁶

We can calculate the pH of a buffer system using the Henderson-Hasselbalch equation.

pH = pKa + log [base]/[acid]

pH = -log 7.1 × 10⁻⁶ + log 0.150 M/0.530 M

pH = 4.6