MCQ
Zinc and mercury do not show variable valency like $d-$ block elements because
- AThey are soft
- ✓Their $d- $ shells are complete
- CThey have only two electrons in the outermost subshell
- DTheir $d-$ shells are incomplete
✓
Answer
Correct option: B.
Their $d- $ shells are complete
b
(b)$_{30}Zn$ and $_{80}Hg$ have their $d$ orbitals completely filled so they do not show any variable valency.
(b)$_{30}Zn$ and $_{80}Hg$ have their $d$ orbitals completely filled so they do not show any variable valency.
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