MCQ
Elements of $3d$ series which does not show variable valency
- A$Fe, \,Zn$
- ✓$Sc, \,Zn$
- C$Mn, \,Zn$
- D$Ti,\, Co$
✓
Answer
Correct option: B.
$Sc, \,Zn$
b
The electronic configuration of zinc is $[Ar] 3 d ^{10} 4 s ^2$.
The electronic configuration of zinc is $[Ar] 3 d ^{10} 4 s ^2$.
It can only lose two electrons from the $4 s$ orbital and show $+2$ oxidation state.
It does not show variable valency.
However, all other transition metals like $Mn , Fe, Cr$ have partially filled $d$ orbitals and hence, show variable valency.
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