Question

Use Lewis Symbols to show electron transfer between the following atoms to form cations and anions:

$\mathrm{K}\mathrm{and}\mathrm{S}$

Answer 1

Lewis symbol:

• In the formation of a molecule, only the outer shell electrons take part in chemical combination and they are known as valence electrons.
• Lewis, an American chemist introduced simple notations to represent valence electrons in an atom. These notations are called Lewis symbols.

Electron transfer between Potassium and Sulfur:

• The atomic number of potassium$\left(\mathrm{K}\right)$ is $19$ so the distribution of electrons of potassium per shell is $\left(2,8,8,1\right)$.
• The atomic number of sulfur$\left(\mathrm{S}\right)$ is $16$ so the distribution of electrons of sulfur per shell is $\left(2,8,6\right)$.
• A metal atom loses one or more electrons to form a cation and a non-metal atom gains one or more electrons to form an anion.

The formation of Potassium sulfide via sharing of electrons is shown below: