IONIC COMPOUNDS:Ionic compounds are compounds made up of ions. These ions are atoms that gain or lose electrons, giving them a net positive or negative charge. Metals tend to lose electrons, so they become cations and have a net positive charge. Non-metals tend to gain electrons, forming anions that have a net negative charge.
In other words, ionic compounds are held together by ionic bonds. Elements can gain or lose electrons in order to attain their nearest noble gas configuration. Formation of ions for the completion of octet helps them gain stability. In a reaction between metals and non-metals, metals generally lose electrons to complete their octet and non-metals gain electrons to complete their octet. Metals and non-metals generally react to form ionic compounds.
Formation of Ionic Compounds : Ionic compounds are also known as electrovalent compounds. The chemical bond formed by the transfer of electrons from one atom to another is known as Ionic bond. These compounds contain ions.
FORMATION OF MAGNESIUM CHLORIDE :
Mg ----------------------------> Mg2+ + 2e-
2Cl + 2e- ----------------------> 2Cl-
Physical nature: Ionic compounds are solids and are somewhat hard because of the strong force of attraction between the positive and negative ions. These compounds are generally brittle and break into pieces when pressure is applied.
Melting and Boiling points: Ionic compounds have high melting and boiling points. This is because a considerable amount of energy is required to break the strong inter-ionic attraction.
Solubility:Ionic compounds are generally soluble in water and insoluble in solvents such as kerosene, petrol, etc.
Conduction of Electricity: The conduction of electricity through a solution involves the movement of charged particles. A solution of an Ionic compound in water contains ions, which move to the opposite electrodes when electricity is passed through the solution. Ionic compounds in the solid state do not conduct electricity because movement of ions in the solid is not possible due to their rigid structure. But ionic compounds conduct electricity in the molten state as the elecrostatic forces of attraction between the oppositely charged ions are overcome due to the heat. Thus, the ions move freely and conduct electricity.