UPSC Combined Geo-Scientist, Mains · 2023 · Mains Paper I
Q8(b). Total hardness of water by EDTA
Question
Enumerate the outline of the procedure for the estimation of total hardness of water using EDTA.
Answer in brief
Titrate Ca²⁺ + Mg²⁺ with standard EDTA at pH 10 using Eriochrome Black T: wine red → blue. Report total hardness as mg L⁻¹ CaCO₃.
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Coverstotal hardness of waterEDTA titrationEriochrome Black Thardness as CaCO3complexometric titration
All parts of Question 8
- 8(a)(i) Cyanide determination with silver nitrate10 marks
- 8(a)(ii) Fraction of fully deprotonated EDTA5 marks
- 8(b) Total hardness of water by EDTA15 marks