COMEDK · Chemistry · 3. Classification of Elements and Periodicity in Properties
Atomic numbers of vanadium, chromium, nickel and iron are \(23,24,28\) and 26 respectively. Which one of these is expected to have the highest second ionisation enthalpy?
- A \(\mathrm{Cr}\)
- B \(\mathrm{V}\)
- C \(\mathrm{Fe}\)
- D \(\mathrm{Ni}\)
Answer & Solution
Correct Answer
(A) \(\mathrm{Cr}\)
Step-by-step Solution
Detailed explanation
Second ionisation enthalpy of \(\mathrm{Cr}\) is highest because after the removal of 1st electron, Cr acquires a stable half-filled \(d^{5}\) configuration thus, removal of 2 nd electron is very difficult.
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