Question

The correct order of ionic radii of $Y^{3+}L{a}^{3+}E{u}^{3+}$ and $L{u}^{3+}$ is
(Atomic nos. $Y=39,La=57,Eu=63,Lu=71$ )

• A. $Y^{3+}<L{a}^{3+}<E{u}^{3+}<L{u}^{3+}$
• B. $Y^{3+}<L{u}^{3+}<E{u}^{3+}<L{a}^{3+}$
• C. $L{u}^{3+}<E{u}^{3+}<L{a}^{3+}<Y^{3+}$
• D. $L{a}^{3+}<E{u}^{3+}<L{u}^{3+}<Y^{3+}$

Answer 1

Answer: (B)

Ongoing from $L{a}^{+3}$ to $L{u}^{+3}$ ion size shrinks due to Lanthanide contraction.