Types of Oxides

Section 1: Basic Oxides

Basic Oxides, also known as Metal Oxides, are typically formed when metals react with oxygen.
They have the ability to react with acids, forming water and a type of salt, showcasing their basic properties.
Basic oxides dissolve in water to form alkaline solutions. The alkalinity of these solutions is due to the presence of hydroxide ions (OH-).
Examples of basic oxides include sodium oxide (Na2O), calcium oxide (CaO), and iron(II) oxide (FeO).
As per their reactivity, not all basic oxides are soluble in water. Those which are soluble form alkalis.

Section 2: Acidic Oxides

Acidic Oxides are mainly formed when non-metals react with oxygen.
Acidic oxides react with bases to form a type of salt and water, which reinforces their acidic nature.
They form acidic solutions when dissolved in water due to the presence of hydrogen ions (H+).
Common examples of acidic oxides are sulphur dioxide (SO2), carbon dioxide (CO2), and nitrogen dioxide (NO2).
Acidic oxides can be harmful or dangerous. For instance, sulphur dioxide and nitrogen dioxide contribute to acid rain which is harmful to the environment.

Section 3: Neutral Oxides

Neutral Oxides show neither basic nor acidic properties, and they do not form salts when they react with acids or bases.
These oxides do not change the colour of litmus paper, indicating their neutrality.
Examples of neutral oxides are nitrous oxide (N2O), carbon monoxide (CO), and water (H2O).

Section 4: Amphoteric Oxides

Amphoteric Oxides are oxides that show both acidic and basic properties. They can react with both acids and bases to form salts.
Important examples of amphoteric oxides include aluminium oxide (Al2O3), zinc oxide (ZnO), and lead(II) oxide (PbO).
They are typically formed when certain metals react with oxygen. Depending on the other substance that they react with, they can behave as either an acid or a base.
Solubility and reactivity can vary between different amphoteric oxides. Aluminium oxide, for example, is insoluble in water but reacts with both strong acid (like HCl) and strong bases (like NaOH) to form salts.