Ncert Exercises & Solutions

Match Column-I with Column-II and choose the appropriate option:

	Column-I (Species)		Column-II (Electronic Configuration)
A.	$Cr$	(i).	$[Ar]3d^84s^0$
B.	$Fe^{2+}$	(ii).	$[Ar]3d^{10}4s^1$
C.	$Ni^{2+}$	(iii).	$[Ar]3d^64s^0$
D.	$Cu$	(iv).	$[Ar]3d^54s^1$
		(v).	$[Ar]3d^64s^2$

Hint: Electronic configuration of Cr is

1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 3 d^{5} 4 s^{1}

A. $Cr (Z = 24) = 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 3 d^{5} 4 s^{1} = [Ar] 3 d^{5} 4 s^{1}$

B. ${Fe}^{2 +} (Z = 26) = 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 3 d^{6} 4 s^{0} = [Ar] 3 d^{6} 4 s^{0}$

C. ${Ni}^{2 +} (Z = 28) = 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 3 d^{8} 4 s^{0} = [Ar] 3 d^{8} 4 s^{0}$

D. $Cu (Z = 29) = 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 3 d^{10} 4 s^{1} = [Ar] 3 d^{10} 4 s^{1}$

	Column-I (Species)		Column-II (Electronic Configuration)
A.	\(Cr\)	(i).	\([Ar]3d^84s^0\)
B.	\(Fe^{2+}\)	(ii).	\([Ar]3d^{10}4s^1\)
C.	\(Ni^{2+}\)	(iii).	\([Ar]3d^64s^0\)
D.	\(Cu\)	(iv).	\([Ar]3d^54s^1\)
		(v).	\([Ar]3d^64s^2\)