Q14 / 180 · COMEDK 2021 · Chemistry
In $3 d$-transition series, which one has the least melting point?
- A$\mathrm{V}$
- Correct answerB$\mathrm{Zn}$
- C$\mathrm{Mn}$
- D$\mathrm{Cu}$
Solution
The melting points of $3d$-transition elements depend on the strength of metallic bonding, which is determined by the number of unpaired electrons available for delocalization. In the $3d$ series, the electronic configuration of Zinc is $[Ar] 3d^{10} 4s^{2}$.
Since all $d$-orbitals are completely filled in Zinc, there are no unpaired electrons available for metallic bonding. Consequently, the interatomic metallic bonds in Zinc are the weakest among the $3d$-transition series elements.
As a result, Zinc exhibits the lowest melting point among the elements of the $3d$-transition series.
Answer: $\mathrm{Zn}$
Since all $d$-orbitals are completely filled in Zinc, there are no unpaired electrons available for metallic bonding. Consequently, the interatomic metallic bonds in Zinc are the weakest among the $3d$-transition series elements.
As a result, Zinc exhibits the lowest melting point among the elements of the $3d$-transition series.
Answer: $\mathrm{Zn}$
Hence, the correct answer is option: 'B'.