Question

Explain the formation of calcium oxide through its orbit structure.

Answer 1

Calcium has an electronic configuration of 2, 8, 8, 2. The number of valence electrons of calcium is 2 and that of oxygen (2, 6) is 6. Therefore, oxygen requires two electrons to complete its octet. Calcium attains noble gas configuration by losing its two valence electrons to oxygen and both form calcium ion, having a +2 charge, and oxide ion, with a –2 charge, respectively. As only one oxygen atom is required to accept two valence electrons donated by the calcium atom, the formula of calcium oxide is CaO.

\[\ce{\underset{\underset{Atom}{(2, 8, 8, 2)}}{Ca} - 2e^- -> \underset{\underset{Cation}{(2, 8, 8)}}{{Ca}^{2+}}}\]

\[\ce{\underset{\underset{Atom}{(2, 6)}}{O} + 2e^- -> \underset{\underset{Anion}{(2, 8)}}{{O}^{2-}}}\]

Orbit structure of electrovalent bonding in CaO.