Answer: Option (a) is the correct answer.
Explanation:
When a bond is formed by sharing of electrons then it is known as a covalent bond and when a bond is formed by transfer of electrons then it is known as an ionic bond.
Atomic number of magnesium is 12 and its electronic configuration is 2, 8, 2. Atomic number of oxygen is 8 and its electronic configuration is 2, 6.
So, in order to attain stability magnesium will lose two electrons and oxygen will gain two electrons. Hence, an ionic bond will be formed.
Thus, we can conclude that the statement they form an ionic bond by exchanging two electrons best describes how magnesium (mg) and oxygen (o) bond.
