Lecture 4 – Nature of Oxides

Nature of Oxides:

There are 3 types of oxides: acidic, basic and amphoteric. The Table below shows the relation between their radical contributing to their nature.

Table 4:

Oxide	Radical	Example(s)
Basic	Metallic	CaO, MgO
Acidic	Non-metallic	SO2, CO2, NO2
Amphoteric	Elements on the staircase line in the Periodic table	Al2O3

Amphoteric Oxides:

The metals on the staircase line in the Periodic table form Amphoteric Oxides. These are unique because they are both; acidic and basic in nature, and undergo neutralization reactions with both acids and bases.

1. Reaction with Acids:
   
   Amphoteric oxides react with acids to form a salt and water.
2. Reaction with Bases/Alkalis:

Amphoteric oxides react with bases to form a salt and water.