Practice question · Numerical answer
A buffer contains equal concentrations of a weak acid and its conjugate base. The acid has . Compute the pH of the buffer.
Hints
- Use the Henderson-Hasselbalch equation.
- When the two concentrations are equal, the logarithm of their ratio is zero.
Show the answer
4.75 (answers within ±0.05 count)
Why
With the ratio is 1 and , so . This is why a buffer is chosen by matching its to the pH you want to hold.
Practise Buffers, Hydrolysis and Titration
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More questions on Buffers, Hydrolysis and Titration
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