NEET2003Chemistryd and f Block ElementsActual
The correct order of ionic radii of Y ³⁺ , La ³⁺ and Lu ³⁺ is: (Atomic nos Y =39, La =57, Eu =63 Lu =71 )
Options
- AY ³⁺ < La ³⁺ < Eu ³⁺ < Lu ³⁺
- BY ³⁺ < Lu ³⁺ < Eu ³⁺ < La ³⁺
- CLu ³⁺ < Eu ³⁺ < La ³⁺ < Y ³⁺
- DLa ³⁺ < Eu ³⁺ < Lu ³⁺ < Y ³⁺
Correct answer
B. Y ³⁺ < Lu ³⁺ < Eu ³⁺ < La ³⁺
Step-by-step solution
Eu and Lu are the members of lanthanide series (so they show lanthanide contraction) and La is the representative element of all elements of such series and Y ³⁺ ion has lower radii as comparison to La ³⁺ because it lies immediately above it in the periodic table. Y ³⁺ < Lu ³⁺ < Eu ³⁺ < La ³⁺