Q. A transition element X has the configuration $\lbrack Ar\rbrack d^{4}$ in its +3 oxidation state. Its atomic number is
A) 25
B) 26
C) 22
D) 19
Explanation
(a)
Given, X=[Ar]$d^{4}$
$\because\$The complete configuration of the ion,
$X^{3 +}\ = 1s^{2},\ 2s^{2}\ ,2p^{6},3s^{2}\ 3p^{6},3d^{4}$
$\therefore\ X = \ 1s^{2},\ 2s^{2}\ ,2p^{6},3s^{2},3p^{6}\ ,3d^{5}\ 4s^{2}$
$\therefore\$The atomic number of the element is 25 and the element is $Mn$.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.