Question

(a) Show the formation of Na₂O by the transfer of electrons between the combining atoms.
(b) Why are ionic compounds usually hard?
(c) How is it that ionic compounds in the sold state do not conduct electricity but they do so when in molten state?
(d) What type of chemical bonds are present in CCl₄?
​(e) What type of chemical bonds are present in MgCl₂?

Answer 1

(a) Electronic configuration of Na₂O.

Formation of ionic bond:


(b) Ionic compounds are usually hard because of inter-atomic attractive forces between them. Positively charged ion and negatively charged ion are strongly attracted towards each other and their lattice enthalpy increases.

(c) Electricity can be conducted only in the presence of free electrons/ions. In the solid state, there will be no free electrons but in the molten state, ions are free to conduct electricity.

(d) In carbon tetrachloride, four single bonds are formed. Hence, covalent bonding is present in CCl₄.

(e) In magnesium chloride, magnesium will lose its electrons and chlorine will accept those electrons to form magnesium chloride. Hence. ionic bonding is present in magnesium chloride.