MHT CET202525 Apr 2025Evening ShiftChemistryd and f Block ElementsActual
Which element from following has smallest ionic size in +3 state?
Options
- ALu
- BLa
- CDy
- DNd
Correct answer
A. Lu
Step-by-step solution
The ionic size of lanthanide M ³⁺ ions decreases steadily across the lanthanide series due to lanthanide contraction . Of the given elements—lanthanum ( Z = 57 ), neodymium ( Z = 60 ), dysprosium ( Z = 66 ), and lutetium ( Z = 71 )—lutetium has the highest atomic number and thus the smallest ionic radius. Lu ³⁺ has the smallest ionic size. The final answer is A .