Question

Select the correct ground state electronic configuration

	$Cr$	$Eu$	$T{i}^{2+}$
(a)	$\left[Ar\right]3d^{5}4s^1$	$\left[Xe\right]4f^{7}5d^{0}6s^2$	$\left[Ar\right]3d^{2}4s^0$
(b)	$\left[Ar\right]3d^{4}4s^2$	$\left[Xe\right]4f^{7}5d^{0}6s^2$	$\left[Ar\right]3d^{2}4s^2$
(c)	$\left[Ar\right]3d^{4}4s^2$	$\left[Xe\right]4f^{6}5d^{1}6s^2$	$\left[Ar\right]4s^{2}4d^0$
(d)	$\left[Ar\right]3d^{5}4s^1$	$\left[Xe\right]3f^{6}5d^{2}6s^1$	$\left[Ar\right]4s^{1}3d^1$

• A. a
• B. b
• C. c
• D. d

Answer 1

Answer: (A)

The correct electronic configuration is :
$Cr(24)=[Ar{]}^{18}3d^{5}4s^1$
$Eu(63)=[Xe{]}^{54}4f^{7}6s^2$
$T{i}^{2+}(22)=[Ar{]}^{18}3d^{2}4s^0$