Question

Show the formation of $\mathrm{MgO}$ by transfer of electrons.

Answer 1

Part 1: Electronic configuration of magnesium:

• The atomic number of Magnesium ($\mathrm{Mg}$) is 12.
• The electronic configuration of magnesium is $1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^{6}3{\mathrm{s}}^2$.

In order to obtain an octet configuration, it will lose two electrons.

Part 2: Electronic configuration of oxygen:

• The atomic number of oxygen $\left(\mathrm{O}\right)$ is 8
• The electronic configuration of oxygen is $1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^4$.

In order to obtain an octet configuration, it has to gain two electrons.

Part 3: Formation of Magnesium oxide $\mathrm{MgO}$:

• When magnesium reacts with oxygen, the magnesium atom transfers its two outermost electrons to an oxygen atom.
• By losing two electrons, the magnesium atoms form a magnesium ion (${\mathrm{Mg}}^{2+}$) and by gaining two electrons, the oxygen atom forms an oxide ion (${\mathrm{O}}^{2-}$) and an ionic bond is formed between $\mathrm{MgO}$.