Answer:
See below
Step-by-step explanation:
The contact process is an Industrial method of producing sulfuric acid.
Step 1. Conversion of S to SO₂
Molten sulfur is burned in an excess of air.
S(ℓ) + O₂(g) ⟶ SO₂(g)
Step 2. Conversion of SO₂ to SO₃
The hot mixture of SO₂ and excess air at about 425 °C and 1.5 atm is passed over a hot V₂O₅ catalyst.
SO₂(s) + O₂(g) ⇌ SO₃(g)
The SO₂ is converted to SO₃ in an equilibrium reaction.
Step 3. Conversion of SO₃ to H₂SO₄
(a) The SO₃ is dissolved in concentrated H₂SO₄ .
SO₃(g) + H₂SO₄(ℓ) ⟶ H₂S₂O₇(ℓ)
The product is fuming sulfuric acid.
(b) Then, enough water is added to react with the dissolved SO₃ and form concentrated H₂SO₄.
H₂O(ℓ) + H₂S₂O₇(ℓ) ⟶2H₂SO₄(ℓ)
