Q 1 :

Which of the following acts as a strong reducing agent?
(Atomic number : Ce = 58, Eu = 63, Gd = 64, Lu = 71)                      [2024]

• ${\mathrm{Lu}}^{3+}$

   

• ${\mathrm{Ce}}^{4+}$

   

• ${\mathrm{Gd}}^{3+}$

   

• ${\mathrm{Eu}}^{2+}$

   

Q 2 :

The number of element from the following that do not belong to lanthanoids is

Eu, Cm, Er, Tb, Yb and Lu                                   [2024]

• 5

   

• 1

   

• 3

   

• 4

   

Q 3 :

The electronic configuration of Einsteinium is

(Given atomic number of Einsteinium = 99)                    [2024]

• $\left[\text{Rn}\right] 5f^{12} 6d^0 7s^2$

   

• $\left[\text{Rn}\right] 5f^{11} 6d^0 7s^2$

   

• $\left[\text{Rn}\right] 5f^{13} 6d^0 7s^2$

   

• $\left[\text{Rn}\right] 5f^{10} 6d^0 7s^2$

   

Q 4 :

Number of colourless lanthanoid ions among the following is _________ .         

${\text{Eu}}^{3+}, {\text{Lu}}^{3+}, {\text{Nd}}^{3+}, {\text{La}}^{3+}, {\text{Sm}}^{3+}$                          [2024]

Q 5 :

Diamagnetic Lanthanoid ions are:                        [2024]

• ${\text{Nd}}^{3+}$& ${\text{Eu}}^{3+}$

   

• ${\text{La}}^{3+}$& ${\text{Ce}}^{4+}$

   

• ${\text{Nd}}^{3+}$& ${\text{Ce}}^{4+}$

   

• ${\text{Lu}}^{3+}$& ${\text{Eu}}^{3+}$

   

Q 6 :

Lanthanoid ions with $4f^7$ configuration are:                 [2025]

(A)   ${\mathrm{Eu}}^{2+}$
(B)   ${\mathrm{Gd}}^{3+}$
(C)   ${\mathrm{Eu}}^{3+}$
(D)   ${\mathrm{Tb}}^{3+}$
(E)   ${\mathrm{Sm}}^{2+}$

• (A) and (B) only

   

• (B) and (C) only

   

• (A) and (D) only

   

• (B) and (E) only

   

Q 7 :

Which of the following ions is the strongest oxidizing agent?

(Atomic Number of Ce = 58, Eu = 63, Tb = 65, Lu = 71)                    [2025]

• ${\mathrm{Lu}}^{3+}$

   

• ${\mathrm{Ce}}^{3+}$

   

• ${\mathrm{Eu}}^{2+}$

   

• ${\mathrm{Tb}}^{4+}$

   

Q 8 :

Which one amongst the following are good oxidizing agents?

A. ${\mathrm{Sm}}^{2+}$  B. ${\mathrm{Ce}}^{2+}$

C. ${\mathrm{Ce}}^{4+}$  D. ${\mathrm{Tb}}^{4+}$

Choose the most appropriate answer from the options given below:                     [2023]

• D only

   

• C and D only

   

• C only

   

• A and B only

   

Q 9 :

${\mathrm{Nd}}^{2+}=$ ____________                    [2023]

• $4f^3$

   

• $4f^{4}6s^2$

   

• $4f^{2}6s^2$

   

• $4f^4$

   

Q 10 :

Which of the following elements have half-filled $f$-orbitals in their ground state?

(Given: atomic number Sm = 62; Eu = 63; Tb = 65; Gd = 64; Pm = 61)         [2023]

(A) Sm
(B) Eu
(C) Tb
(D) Gd
(E) Pm

Choose the correct answer from the options given below:

• A and B only

   

• C and D only

   

• B and D only

   

• A and E only