Question

Identify the element having highest enthalpy of atomisation from following.

Options

• Sc (Z = 21)

• Fe (Z = 26)

• Zn (Z = 30)

• Cu (Z = 29)

Answer 1

Fe (Z = 26)

Explanation:

The atomisation enthalpy of iron (Fe) is the highest. It is determined by the strength of the metallic connection, which is in turn determined by the amount of unpaired electrons. The metallic link will be stronger as the number of unpaired electrons increases. In the electronic configuration of Fe (Z = 26), four unpaired electrons are present.

Fe = 1s², 2s², 2p⁶, 3s², 3p⁶, 3d⁶, 4s²

Valence electron	3d6				4s2
	⌉⌊	⌉	⌉	⌉	⌉⌊

Number of unpaired electrons = 4