Question

give reasons for the following: 1) Ionic compounds are usually hard. 2) Sodium chloride has a high melting point.

Answer 1

Ionic compounds are usually hard as the ions present in the ionic compounds are held together by the strong electrostatic forces of attraction.

Sodium chloride has a high melting and boiling point. There are strong electrostatic attractions between the positive and negative ions, and it takes a lot of heat energy to overcome them. Ionic substances allhave high melting and boiling points