Question

Among the following, basic oxide is:

• A. SO₃
• B. SiO₂
• C. CaO
• D. Al₂O₃

Answer 1

The Correct Option is C

To identify the basic oxide among the given options, we first need to understand what constitutes a basic oxide.

Definition:

• Basic oxides are oxides that react with acids to form salt and water. They are usually formed by metals.

Options Analysis:

1. SO₃: Sulfur trioxide is an acidic oxide. It reacts with water to form sulfuric acid (H₂SO₄).
2. SiO₂: Silicon dioxide is largely neutral but can react with strong bases, making it slightly acidic. It is not a basic oxide.
3. CaO: Calcium oxide, also known as quicklime, is a basic oxide. It reacts with water to form calcium hydroxide (Ca(OH)₂), which is a strong base.
4. Al₂O₃: Aluminum oxide is amphoteric, meaning it can react with both acids and bases. However, it does not qualify as a purely basic oxide.

Conclusion:

Among the options provided, CaO (Calcium oxide) is the basic oxide, as it forms a strong base when reacting with water.