JEE Mains · Chemistry · STD 12 - 4. d and f- block elements
The number of valence electrons present in the metal among \(\mathrm{Cr}, \mathrm{Co}, \mathrm{Fe}\) and Ni which has the lowest enthalpy of atomisation is _______.
- A \(8\)
- B \(9\)
- C \(6\)
- D \(10\)
Answer & Solution
Correct Answer
(C) \(6\)
Step-by-step Solution
Detailed explanation
Out of \(\mathrm{Cr}, \mathrm{Co}, \mathrm{Fe}\) and \(\mathrm{Ni}\) Chromium has lowest heat of atomisation. \(\mathrm{Cr}=[\mathrm{Ar}] 3 \mathrm{~d}^5 4 \mathrm{~s}^1\) \(\because\) Total six valence \(\mathrm{e}^{-}\)in \(\mathrm{Cr}\).
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