UPSC Combined Geo-Scientist, Mains · 2026 · Mains Paper I
Q8(a). The [MCl₄]²⁻/[M(H₂O)₆]²⁺ equilibrium: identify M
Question
In the following equilibrium [MCl₄]²⁻ + 6H₂O ⇌ [M(H₂O)₆]²⁺ + 4Cl⁻, find M assuming that the magnetic moments of [MCl₄]²⁻ and [M(H₂O)₆]²⁺ are 3.87 BM and 4.1 BM respectively. What will be the colour of these complexes, and why is the equilibrium shifted upon addition of Zn²⁺ or Ca²⁺ ions to the reaction medium?
Model answer
The free solution for 2026 answers the questions picked in its time plan. Question 8 is answered in full in the Book Edition of the 2026 solutions of Geo-Scientist Chemistry Paper I.
Coversmagnetism and colourThe [MCl₄]²⁻/[M(H₂O)₆]²⁺ equilibriumidentify M
All parts of Question 8
- 8(a) The [MCl₄]²⁻/[M(H₂O)₆]²⁺ equilibrium: identify M10 marks
- 8(b) Metal–metal bond order in dimeric organometallics10 marks
- 8(c) Half-life of radium-226 from alpha emission10 marks