The contact process Flashcards
What is the purpose of the contact process?
To make sulphuric acid from sulfur
What is the first stage in the contact process?
Molten sulfur is burned in air to make sulfur dioxide
Word and symbol equations for step 1?
sulfur + oxygen → sulfur dioxide
S +O2 → SO2
What is stage 2 in the contact process?
Sulfur dioxide reacted with oxygen to make sulfur trioxide
What kind of reaction is in stage 2?
A reversible reaction
What catalyst is used in stage 2
Layers of Vanadium (v) oxide
What is stage 3?
Sulfur trioxide is converted into oleum
How is sulfur trioxide converted to oleum?
It is added to concentrated sulfuric acid
Word and symbol equations for step 3?
Sulfur trioxide + sulfuric acid → oleum
SO3 + H2SO4 → H2S2O7
Why is sulfur trioxide dissolved in 98% H2SO4 ?
Reacting it directly with water would produce a sulfuric acid mist. This mist cannot be condensed and pollutes the air
What is stage 4?
Oleum is converted into sulfuric acid
Word and symbol equation for stage 4
Oleum + water → sulfuric acid
H2S2O7 + H2O → 2H2SO4
Uses of sulfuric acid
Detergents, car batteries, dyes, paints, cleaning metals
How can altering the pressure in stage 2 produce more sulphuric acid?
Increasing pressure makes the equilibrium shift to the right-hand side, where there is a lower pressure as there are fewer moles of gas.
Compromised temperature used in stage 2
450 degrees Celsius
