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MHT CET202016 Oct 2020Morning ShiftChemistryThermodynamics (C)Actual

Identify the element having highest enthalpy of atomization from following.

Options

  1. ACu (Z=29)
  2. BFe (Z=26)
  3. CZn(Z=30)
  4. DSc (Z=21)

Correct answer

B. Fe (Z=26)

Step-by-step solution

Fe (Z=26) 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 =1 ~s ², 2 ~s ², 2 p ⁶, 3 ~s ², 3 p ⁶, 3 ~d ⁶, 4 ~s ² Number of unpaired electrons =4

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