The metallic bond is defined as a bond formed between metal atoms (positively charged ions) due to mobile or free electrons.
(i) Ionic compounds are mostly crystalline solids at room temperature.
(ii) Ionic compounds in solid state have negligible electrical conductance but they are good conductors in solution and in the molten form.
(iii) Ionic compounds have high melting and boiling points.
(iv) They dissolve easily in polar solvents like water.
(i) They have usually low melting and boiling points.
(ii) They are usually bad conductors of electricity.
(iii) They are usually insoluble in water but are soluble in non-aqueous solvents like benzene, gasoline, alcohol and acetone.
(iv) Large molecules of covalent crystals which are very stable and hard. They have very high melting and boiling points.
(i) They are soluble in water.
(ii) They usually conduct electricity.
(iii) They are soluble in polar solvents.
(iv) They are insoluble in non-polar solvents.
(i) They are insoluble in water.
(ii) They usually do not conduct electricity.
(iii) They are insoluble in polar solvents.
(iv) They are soluble in non-polar solvents.
(i) All metals except mercury are solid.
(ii) They have very high melting and boiling points.
(iii) They have metallic lustre.
(iv) Metals are generally ductile and malleable.
(v) When we hit the metal with a hammer they produce a sonorous sound.