Question

why are metallic elements which form ionic oxides basic and why are non-metal oxides which are covalent acidic?

Answer 1

Metallic elements which form ionic oxides basic and non- metal oxides which are covalent acidic. This can be proven by the Litmus Paper Test,where metal oxides whille reacting with water will form strong bases and turn red litmus paper into blue . While ,non metal oxides reacting with water will form strong acids that turn blue litmus paper to red.

Basically , Ionic bond formed between metal and a non metal. And Covalent bond formed between non metal and non metal.

1)Metallic elements which form ionic oxides are basic.

Reason:

Metallic acids are basic in nature because they react with dilute acids and form salt and water. Also they react with water and form metal hydroxides which are alkaline in nature. Because metal hydroxides release " OH- " ions in solution.

eg:   MgO+H2O→Mg(OH)2

2)Non-metallic oxides are covalent acidic

Reason:

Non metallic acids on reacting with water to form acidic solutions which liberate " H+ " ions in solution. Therefore , non metallic oxides would be acidic in nature.

eg:   HCl + H2O ——-> H3O+ + Cl-

Whenever " H+ " ions react with water to form hydronium ions (H3O+), energy is released. Strong acids, which dissociate rapidly and completely, may liberate a large amount of H+ ions in a very short time.