UPSC Combined Geo-Scientist, Mains · 2026 · Mains Paper I
Q8(b). Metal–metal bond order in dimeric organometallics
Question
Among the following organometallic compounds, which one will have the maximum number of bonds between the two metal centres, and a least number of d-electrons at the metal centre? (i) (η⁵-C₅H₅)₂Ni₂(CO)₂ (ii) V₂(CO)₁₂ (iii) (η⁵-C₅H₅)₂Re₂(μ₂-CO)₃ (iv) (η⁵-C₅H₅)₂Re₂(μ₂-O)₂(O)₂
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.
CoversM–M bonds and electron countMetal–metal bond order in dimeric organometallics
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