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UPSC Combined Geo-Scientist

Chemist

  • 3 descriptive papers
  • 200 marks each
  • 3 h per paper

Mains Paper III covers analytical and organic chemistry.

UPSC Combined Geo-Scientist, Mains · 2017 · Mains Paper III

Q4(b). Free nickel with excess EDTA

Question

Mix 50.0 mL of 0.0300 M Ni²⁺ with 50.0 mL of 0.0500 M EDTA at pH 3.0. Given Kf=4.2×10¹⁸ and α₄=2.51×10⁻¹¹, find free Ni²⁺.

Answer in brief

[Ni²⁺]≈1.42×10⁻⁸ M.

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CoversFree nickel with excess EDTAComplexometric equilibrium

All parts of Question 4