Question

The nature of the chemical bond in MgO is:
(A) Electrovalent
(B) Covalent
(C) Dative
(D) Polar Covalent

Answer 1

To solve the given question you must be aware of different types of bonding between atoms which are:
-Ionic bonding: In ionic bonding, the chemical bond is formed by the transfer of electrons from one atom to another to complete its octet.
-Covalent bonding: In covalent bonding, the chemical bond is formed by the sharing of electrons between two or more atoms to complete its octet.
-Metallic bonding: In metallic bonding, the bond is formed by sharing a cloud of electrons between many metal ions. This bonding leads to several properties in metals such as luster, ductility, malleability etcetera.

Complete step by step answer:
-In the MgO molecule, the type of bond that is formed between Mg and O atoms is an ionic bond via the transfer of electrons.
-Mg atoms have 12 electrons. Its electronic configuration is 2, 8, 2. Hence, Mg has 2 electrons in its valence shell which it wants to donate to achieve the noble gas configuration of Neon.
O Atom has 8 electrons. Its electronic configuration is 2, 6. Hence, Oxygen has 6 electrons in its valence shell and it wants 2 more electrons to complete its octet to achieve the noble gas configuration of Neon.
-Now, Mg will transfer its 2 valence electrons to O and will form $M{g^{2 + }}$ cation and O after getting 2 electrons will form $O_{}^{2 - }$ anion and both atoms will complete their octet by forming an ionic bond between them.
$Mg \to {M^{2 + }} + 2e -$
$O + 2{e^ - } \to {O^{2 - }}$
Hence, Option (A) is correct.

Note: Mg is a metal and O is a non-metal. The bond between a metal and non-metal is always formed by the transfer of electrons. The nature of the bond is electrovalent or ionic. While forming the bond one must always take care of the electronic configuration of atoms in the excited state as sometimes incorrect configuration leads to the formation of the wrong molecule.