Q. Number of unpaired electrons in $Mn^{4+}$ is :
Delhi UMET/DPMTDelhi UMET/DPMT 2005
Solution:
Write the electronic configuration of $Mn$ in ground state then
$Mn^{4+}$
Draw the orbitals to find unpaired electrons.
$Mn- (At. no. =25)$
$=1 s^{2}, 2 s^{2}, 2 p^{6}, 3 s^{2}, 3 p^{6}, 4 s^{2} 3 d^{5}$
$\therefore M n^{4+} 1 s^{2}, 2 s^{2}, 2 p^{6}, 3 s^{2}, 3 p^{6}, 4 s^{0}, 3 d^{3}$
$\therefore M n^{4+}$ has three unpaired electrons.
