The Contact Process (5) Flashcards
The first stage of the contact process involves forming ___________ dioxide gas. This is usually done by burning _________ in air or roasting __________ ores
Sulfur
Sulfur
Sulfide
Equation for the first stage of contact process:
S + O2 –> SO2
Stage 2: The sulfur dioxide is then ____________ (with the help of a __________) to form sulfur ______________ gas
Oxidised
Catalyst
Trioxide
Equation for the second stage of contact process:
2SO2 + O2 ↔ 2SO3
Stage 3: Next the sulfur _____________ is dissolved in concentrated __________ acid to form liquid ________
Trioxide
Oleum
Sulfuric
Equation for the third stage of contact process:
SO3 + H2SO4 –> H2S2O7
Stage 4: Finally, ________ is diluted with measure amounts of __________ to form concentrated ___________ acid
Oleum
Water
Sulfuric
Equation for fourth stage of contact process:
H2S2O7 + H2O–> 2H2SO4
A _________ is important when making SO3
Catalyst
Step 2 of the contact process is ______thermic (which means it _______ _____ heat). Also there are 2 moles compared to 3 moles of reactants (so the product has ________ volume than the reactants)
Exothermic
Gives out
Less
To get the maximum yield, the obvious thing to do would be to reduce the temperature and increase the pressure. What is the problem with this?
Reducing the temperature slows the rate of the reaction right down.
The key thing with the contact process is to use a ___________
Catalyst
What is the catalyst used in the contact process
Vanadium(V) oxide catalyst, V2O5
What is the ideal temperature for the contact process
450°C
What is the ideal pressure for the contact
2 Atmospheres
