Oxide Q reacts with both acid and base, indicating amphoteric nature

Steps:

• Acidic oxides react only with bases to form salt and water.
• Basic oxides react only with acids to form salt and water.
• Amphoteric oxides react with both acids and bases to form salt and water.
• Oxide Q reacts with HCl (acid) and KOH (base), producing salt and water in both, matching amphoteric behavior.

Why B is correct:

• Amphoteric oxides, like Al2O3, react with acids (e.g., Al2O3 + 6HCl → 2AlCl3 + 3H2O) and bases (e.g., Al2O3 + 2KOH + 3H2O → 2KAl(OH)4), forming salts and water.

Why the others are wrong:

• A: Acidic oxides, like CO2, do not react with acids like HCl.
• C: Basic oxides, like MgO, do not react with bases like KOH.
• D: Non-metal oxides are typically acidic and do not react with acids.

Final answer: B