Question

Which 3d series of element has least enthalpy of atomization?

• A. Sc
• B. Mn
• C. V
• D. Cu
• E. Zn

Hint:

The enthalpy of atomization in transition metals is influenced by the nature of their metallic bonds. Full d-orbitals generally lead to more stable bonds, thus lowering the enthalpy of atomization.

Answer 1

The Correct Option is D

Step 1: Understanding the concept of enthalpy of atomization.
Enthalpy of atomization refers to the energy required to convert one mole of atoms from a solid to a gaseous state. This value is typically lower for elements with strong metallic bonds.
Step 2: Atomic and bonding properties.
The 3d transition metals show varied enthalpy of atomization due to differences in their atomic structures and bonding. Elements like Cu exhibit stronger metallic bonds due to their filled d-orbitals, which reduce the enthalpy of atomization.
Step 3: Comparison with other elements.
\begin{itemize} \item (A) Sc: Scandium has a higher enthalpy of atomization due to weaker metallic bonding as compared to Cu. \item (B) Mn: Manganese has relatively high enthalpy of atomization due to the complexity of its bonding. \item (C) V: Vanadium also has a relatively high enthalpy due to similar reasons as Mn. \item (D) Cu: Correct. Copper has a lower enthalpy of atomization because of its filled d-orbitals, which stabilize the metallic bond. \item (E) Zn: Zinc has weaker metallic bonds compared to copper, but it is still higher than copper's enthalpy of atomization. \end{itemize}
Step 4: Conclusion.
Therefore, the element with the least enthalpy of atomization in the 3d series is copper (Cu).
Final Answer: Cu.