JEE Mains · Chemistry · STD 12 - 4. d and f- block elements
Pairs of elements with the same number of electrons in their respective 4f orbital are
[Atomic number. Eu-63, Gd-64, Dy-66, Ho-67, Tm-69, Yb-70, Lu-71, Hf-72]
A. (Eu and Gd)
B. (Dy and Ho)
C. (Yb and Hf)
D. (Lu and Tm)
Choose the correct answer from the options given below:
- A B and C Only
- B A and B Only
- C A and D Only
- D A and C Only
Answer & Solution
Correct Answer
(D) A and C Only
Step-by-step Solution
Detailed explanation
The electronic configurations of the given elements are: Eu (63): [Xe] \(4f^7 6s^2\) Gd (64): [Xe] \(4f^7 5d^1 6s^2\) Dy (66): [Xe] \(4f^{10} 6s^2\) Ho (67): [Xe] \(4f^{11} 6s^2\) Tm (69): [Xe] \(4f^{13} 6s^2\) Yb (70): [Xe] \(4f^{14} 6s^2\) Lu (71): [Xe] \(4f^{14} 5d^1 6s^2\)…
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