Chemistry - CHEMICAL BONDING Question with Solution | TestHub
For the hypothetical isolated ion C₂²⁺ use the light-diatomic ordering π₂ₚ below σ₂ₚ, with z as the internuclear axis. The core and 2s orbitals are filled normally. Three proposed valence-p arrangements are I: (πₓ)²(π)⁰; II: (πₓ)¹(π)¹ with parallel spins; III: (σ)². Which statement is correct for this specified model?
Options:
Answer:
Solution:
C₂²⁺ has ten electrons: four core, four in σ₂ₛ/σ*₂ₛ, and two in the p-bonding set. Their placement in degenerate π orbitals follows Hund's rule in II, giving two unpaired electrons. I pairs prematurely; III bypasses the lower π set. In each case the two 2s bonding and two 2s antibonding electrons cancel and the two p-bonding electrons give bond order 1. Thus A is false; even electron count does not force paramagnetism, and the supplied ordering cannot be overridden by a slogan about overlap.
