NEETChemistryd and f Block Elements
Match List-I with List-II. List-I (Observation) List-II (Reason) A. Similar atomic size of Mo and W 1. Lanthanoid contraction B. Ce ⁴⁺ acts as a strong oxidant 2. Tendency to attain +3 oxidation state C. Greater element-to-element contraction in actinoids 3. Poorer shielding by 5f electrons than 4f electrons D. Zn, Cd and Hg are soft metals 4. Absence of unpaired electrons for metallic bonding Choose the correct answ
Options
- AA-3, B-2, C-1, D-4
- BA-1, B-4, C-3, D-2
- CA-1, B-2, C-3, D-4
- DA-3, B-4, C-1, D-2
Correct answer
C. A-1, B-2, C-3, D-4
Step-by-step solution
A. The similar atomic size of Mo (4d series) and W (5d series) is a direct consequence of lanthanoid contraction. B. Ce ⁴⁺ acts as a strong oxidant because it readily accepts an electron to attain the most stable +3 oxidation state characteristic of lanthanoids. C. The actinoid contraction is greater from element to element than the lanthanoid contraction due to the poorer shielding effect of 5f electrons compared to 4f electrons. D. Zn, Cd and Hg have completely filled d-orbitals ( d ¹⁰ ) and lack unpaired electro