Question

The correct order of ionic radius for $Y^{3+},L{a}^{3+},E{u}^{3+}$ and $L{u}^{3+}$ is:

• 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

The correct option is B $Y^{3+}<L{u}^{3+}<E{u}^{3+}<L{a}^{3+}$

As we move from left to right in a row, size decreases and as we move down in a group, size increases. so radii order is
$Y^{3+}<L{u}^{3+}<E{u}^{3+}<L{a}^{3+}$.