UPSC Combined Geo-Scientist, Mains · 2021 · Mains Paper I
Q6(c). Weak diprotic base titrated with strong acid
Question
Sketch the general appearance of the curve for the titration of a weak diprotic base with strong acid. Explain different regions of the curve.
Answer in brief
For well-separated protonation steps, the falling pH curve has two buffer regions and equivalence points at one and two acid equivalents.
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Coverstitration curvediprotic basestrong acid titrationbuffer regionequivalence pointpolyprotic
All parts of Question 6
- 6(a) Acid required by an equimolar carbonate mixture10 marks
- 6(b) Methyl-red colour and ionisation10 marks
- 6(c) Weak diprotic base titrated with strong acid10 marks