Oxide of sodium is basic but oxide of chlorine is acidic why?

The chemical behavior of oxides (acidic, basic, amphoteric, or neutral) depends largely on the nature of the element (metal or non-metal) and its electronegativity.

• Sodium (Na): A highly electropositive alkali metal.
  • Forms Na₂O (sodium oxide).
  • When Na₂O reacts with water: Na₂O + H₂O → 2NaOH
  • NaOH is a strong base, so Na₂O is a basic oxide.
• Chlorine (Cl): A highly electronegative non-metal.
  • Forms oxides like Cl₂O, Cl₂O₇.
  • Example: Cl₂O₇ + H₂O → 2HClO₄ (perchloric acid).
  • Hence, oxides of chlorine are acidic.

Reason for Difference:

• Metals (like sodium) → low electronegativity → form ionic oxides → react with water to give bases.
• Non-metals (like chlorine) → high electronegativity → form covalent oxides → react with water to give acids.

Key Takeaways:

• Na₂O = basic oxide.
• Cl₂O, Cl₂O₇ = acidic oxides.
• Nature of oxide depends on metallic vs non-metallic character.