Industrial equilibria: Contact Process
I can describe the Contact Process for the production of sulfuric acid, explain the importance of each step, and describe the conditions used.
Industrial equilibria: Contact Process
I can describe the Contact Process for the production of sulfuric acid, explain the importance of each step, and describe the conditions used.
These resources will be removed by end of Summer Term 2025.
Lesson details
Key learning points
- The Contact Process involves the production of sulfur trioxide (SO₃) from sulfur dioxide (SO₂) using a catalyst.
- The process has three main stages: burning sulfur to produce SO₂, converting SO₂ to SO₃, then converting SO₃ to H₂SO₄.
- The conversion of SO₂ to SO₃ is a reversible reaction performed at 1-2 atmospheres and 450°C, using a V₂O₅ catalyst.
- Sulfuric acid production is energy-intensive and releases large amounts of CO₂, contributing to global emissions.
- Sulfuric acid is vital for various industries, such as: fertilisers, chemical manufacturing, and petroleum refining.
Keywords
Raw material - The starting materials used to make products are known as the raw materials.
Feedstock - Refers to raw materials used in chemical processes to produce other substances.
Contact process - An industrial method for producing sulfuric acid by oxidising sulfur dioxide to sulfur trioxide.
Exothermic - A type of reaction in which energy is transferred from the reactants to the surroundings.
Corrosive - A substance that causes damage by chemical action, often resulting in severe injury or destruction.
Common misconception
Students often assume that the production of sulfuric acid in the Contact Process is a one-step process (similar to the Haber process).
Clarify that the Contact Process involves multiple stages, each requiring specific conditions. Emphasise the importance of these conditions in maximising yield and minimising energy consumption.
To help you plan your year 11 chemistry lesson on: Industrial equilibria: Contact Process, download all teaching resources for free and adapt to suit your pupils' needs...
To help you plan your year 11 chemistry lesson on: Industrial equilibria: Contact Process, download all teaching resources for free and adapt to suit your pupils' needs.
The starter quiz will activate and check your pupils' prior knowledge, with versions available both with and without answers in PDF format.
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Equipment
None required.
Licence
Starter quiz
6 Questions




Exit quiz
6 Questions
Contact process -
industrial method making sulfuric acid from sulfur, oxygen and water
corrosive -
causing severe injury, damage or destruction by chemical action
exothermic reaction -
reaction in which energy is transferred from reactants to surroundings
feedstock -
raw materials used in chemical processes to make other substances
Haber process -
industrial method for making ammonia from nitrogen and hydrogen
raw materials -
any starting materials used to make any kind of products