D-And F-Block Elements Ques 251
Question: The number of d-electrons in $ F{{e}^{2+}} $ (at no. of $ Fe=26 $ ) is not equal to that of the
[MNR 1994]
Options:
A) p - electrons in Ne (at. no. = 10)
B) s - electrons in $ Mg $ (at. no. = 12)
C) d - electrons in $ Fe $
D) p - electrons in $ C{{l}^{-}} $ (at. no. of $ Cl=17 $ )
Show Answer
Answer:
Correct Answer: D
Solution:
p-electrons in $ C{{l}^{-}} $ (atomic no. of $ Cl=17 $ ) $ C{{l}^{-}},\to ,1s^{2}2s^{2}2p^{6}3s^{2}3p^{6} $
$ F{{e}^{2+}},\to ,1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{6} $
In $ F{{e}^{+2}} $ total number of $ d{{e}^{-}}=6 $ which is not equal to $ p{{e}^{-}} $ in $ C{{l}^{-}}=12 $ .
