4f electron shielding and +3 stability in lanthanoids (4f electrons are core-like; ionization to +3 common; 4f does not shield well)
jee-mainjee-advancedneet-ug
4f electrons are core-like; ionization to +3 common; 4f does not shield well
When to use this
Most Ln show +3; few +2/+4 exceptions (Ce⁴⁺, Eu²⁺, etc.) — JEE focuses on +3 dominance.