91Ó°ÊÓ

When an atom loses an electron from its valence shell then a positively charged species is formed and is called cation.

The charge on the cation represents the number of electrons lost by it.

The given electronic configuration is\({\bf{1}}{{\bf{s}}^{\bf{2}}}{\bf{2}}{{\bf{s}}^{\bf{2}}}{\bf{2}}{{\bf{p}}^{\bf{6}}}{\bf{3}}{{\bf{s}}^{\bf{2}}}{\bf{3}}{{\bf{p}}^{\bf{6}}}{\bf{3}}{{\bf{d}}^{{\bf{10}}}}{\bf{4}}{{\bf{s}}^{\bf{2}}}{\bf{4}}{{\bf{p}}^{\bf{6}}}{\bf{4}}{{\bf{d}}^{\bf{5}}}\).

If it has +2 charge, then the atom’s original electronic configuration becomes

\({\bf{1}}{{\bf{s}}^{\bf{2}}}{\bf{2}}{{\bf{s}}^{\bf{2}}}{\bf{2}}{{\bf{p}}^{\bf{6}}}{\bf{3}}{{\bf{s}}^{\bf{2}}}{\bf{3}}{{\bf{p}}^{\bf{6}}}{\bf{3}}{{\bf{d}}^{{\bf{10}}}}{\bf{4}}{{\bf{s}}^{\bf{2}}}{\bf{4}}{{\bf{p}}^{\bf{6}}}{\bf{4}}{{\bf{d}}^{\bf{7}}}\).

The atom with this electronic configuration has the atomic number 43.

The element is Tc.

The symbol is\(T{c^{2 + }}\).

The given electronic configuration is\({\bf{1}}{{\bf{s}}^{\bf{2}}}{\bf{2}}{{\bf{s}}^{\bf{2}}}{\bf{2}}{{\bf{p}}^{\bf{6}}}{\bf{3}}{{\bf{s}}^{\bf{2}}}{\bf{3}}{{\bf{p}}^{\bf{6}}}{\bf{3}}{{\bf{d}}^{{\bf{10}}}}{\bf{4}}{{\bf{s}}^{\bf{2}}}{\bf{4}}{{\bf{p}}^{\bf{6}}}{\bf{4}}{{\bf{d}}^{\bf{5}}}\).

If it has +2 charge, then the atom’s original electronic configuration becomes

\({\bf{1}}{{\bf{s}}^{\bf{2}}}{\bf{2}}{{\bf{s}}^{\bf{2}}}{\bf{2}}{{\bf{p}}^{\bf{6}}}{\bf{3}}{{\bf{s}}^{\bf{2}}}{\bf{3}}{{\bf{p}}^{\bf{6}}}{\bf{3}}{{\bf{d}}^{{\bf{10}}}}{\bf{4}}{{\bf{s}}^{\bf{2}}}{\bf{4}}{{\bf{p}}^{\bf{6}}}{\bf{4}}{{\bf{d}}^8}\).

The atom with this electronic configuration has the atomic number 44.

The element is Ru.

The symbol is\(R{u^{3 + }}\).