Match the property given in Column I with the element given in Column II.

Column I

(Property)

Column II

(Element)

A.

Lanthanoid which shows + 4 oxidation state

1.

Pm

B. 

Radioactive lanthanoid

2.

Ce

C. 

Lanthanoid which has 4f7 electronic configurations in +3 oxidation state

3.

Lu

D.

Lanthanoid which has 4f14 electronic configurations in +3 oxidation state

4.

Gd

Codes:

Options:   A    B    C    D  
1. 2 4 1 3
2. 1 2 3 4
3. 2 1 4 3
4. 4 1 3 2

 


Hint: Cerium shows +3 and +4 oxidation state
A.
Lanthanoid which shows +4 oxidation state is cerium.
C58e = Xe4f25d06s2 ; Oxidation state = +3 , +4
B.
Lanthnoid which has 4f7 electronic configuration in +3 oxidation state is gadolinium.
G64d = [Xe]4f75 d16s2; Oxidation state = +3
C. 
Radioactive lanthanoid is promethium.  It is the only synthetic (man-made) radioactive lanthanoid.
D.
Lanthanoid which has 4f14 electronic configuration in +3 oxidation state is lutetium
L71u = [Xe]4f145 d16s2; Oxidation state = +3

Hence, option third is the correct answer.