Question

Match Column-I with Column-II.

Column I		Column II
A	Lanthanide hard as steel.	p	Lu
B	Lanthanide with maximum paramagnetic character in $L{n}^{4+}$ state.	q	Tb
C	Lanthanide with maximum value of $E^{\circ }$ for reaction $L{n}^{3+}(aq)+3e^{-}\to Ln(s)$.	r	Sm
D	Lanthanide whose $L{n}^{3+}$ ion is diamagnetic in nature	s	Eu

• A. A - (r), B - (s), C - (p), D - (q)
• B. A -(r),B -(q ), C -(s ),D -(p )
• C. A - (s), B - (r), C - (q), D - (p)
• D. A - (r), B - (s), C - (q), D - (p)

Answer 1

Answer: (B)

(A) Sm is hard as steel.
(B) $T{b}^{4+}$ has $4f^7$ configuration $(7$ unpaired electrons) and thus maximum paramagnetic character.
(C) $Eu$ has maximum value of $E^{\circ }$ for reaction:
$E_u^{3+}(aq)+3^{-}\to Eu(s);E^{\circ }=-2.0V$.
(D) $L{u}^{3+}$ is diamagnetic as it has $4f^{14}$ configuration.