Question

Show the formation of lithium ion.(Atomic number of Li = 3)

Answer 1

Definition of valency.

The number of valence electrons lost or gained by an atom in order to attain stability is called valency.

The atomic number of lithium = 3

Electronic configuration = 2,1

since lithium has one electron in its outermost shell, it does not have stable electronic configuration.

Lithium loses its one electron and achieve the stable configuration as 2

$$\begin{gathered} \mathrm{Li}-1\mathrm{e}{}^{-}\to {\mathrm{Li}}^{+} \\ 2,12 \end{gathered}$$

A lithium atom(K) has 3 protons and 3 electrons. On losing one electron, it becomes a lithium ion(${\mathrm{Li}}^{+}$).