Em tham khảo nha :
\(\begin{array}{l}
a)\\
Che\,{M^{2 + }}:1{s^2}2{s^2}2{p^6}3{s^2}3{p^6}3{d^{10}}4{s^2}4{p^6}\\
Che\,M:1{s^2}2{s^2}2{p^6}3{s^2}3{p^6}3{d^{10}}4{s^2}4{p^6}5{s^2}\\
b)\\
Che\,{X^{3 - }}:1{s^2}2{s^2}2{p^6}3{s^2}3{p^6}3{d^{10}}4{s^2}4{p^6}\\
Che\,X:1{s^2}2{s^2}2{p^6}3{s^2}3{p^6}3{d^{10}}4{s^2}4{p^3}\\
{Z_X} = 33\\
\Rightarrow X:Asen(As)
\end{array}\)