Question

Arrange the following oxides in correct order of their acidic character:
\[ I: N_2O_3, \quad II: P_2O_3, \quad III: N_2O_5, \quad IV: As_2O_3 \]

• A. I > III > II > IV
• B. III > I > II > IV
• C. IV > II > I > III
• D. III > I > IV > II

Hint:

Oxides of non-metals with higher oxidation states are more acidic; acid strength decreases down a group.

Answer 1

The Correct Option is B

Step 1: Higher oxidation state of N gives more acidic oxide.
N\(_2\)O\(_5\) (N = +5) is more acidic than N\(_2\)O\(_3\) (N = +3).

Step 2: Compare across Group 15 elements.
N is more electronegative than P, which is more electronegative than As, so acidic character decreases down the group at the same oxidation state. Final order: N\(_2\)O\(_5\) (III) \(>\) N\(_2\)O\(_3\) (I) \(>\) P\(_2\)O\(_3\) (II) \(>\) As\(_2\)O\(_3\) (IV).
\[ \boxed{III > I > II > IV} \]