Question

Which of these is the key compound for the laboratory preparation of sulphuric acid?

• A. Sulphur dioxide
• B. Sulphur trioxide
• C. Nitric oxide
• D. Sulphur monoxide

Answer 1

The correct option is A

Sulphur dioxide

Sulphur dioxide formed during burning of fossil fuels is the key compound for the laboratory preparation of sulphuric acid. Nitric acid is another compound used for the laboratory preparation of sulphuric acid.

S(s) + O₂(g) → SO₂(g)
2SO₂(g) + O₂(g) → 2SO₃(g)