The Contact Process

Question 1

What is the purpose of the contact process

Answer 1

To make sulphuric acid

Question 2

5 uses of sulphuric acid

Answer 2

1. Used as an industrial acid
2. Lead acid batteries in cars
3. Waste water purification
4. Fertiliser (ammonium sulphate)
5. Refining ores

Question 2

Step 1 of the contact process method 1

Answer 2

Burn sulphur in excess air

S + O2 –> SO2

Question 3

Simple 3 step process for contact process

Answer 3

1. Produce sulphur dioxide (2 methods)
2. Convert sulphur dioxide to subdue trioxide (reversible reaction)
3. Convert sulphur trioxide into sulphuric acid

Question 4

Step 1 of the contact process method 2

Answer 4

Heat sulfides in excess air

4FeS2 + 11O2 –> 2Fe2O3 + 8SO2

Question 5

Step 2 of the contact process

Answer 5

Making sulphur dioxide dugout trioxide

2SO2 + O2 2SO3

Question 6

Conditions for step 2 of the contact process

Answer 6

Temperature = 400-450
Pressure= 1-2 atmospheres 
Catalyst= vanadium oxide

Question 7

Step 3 of the contact process

Answer 7

Turn sulphur trioxide to sulphuric acid 
to make oleum 
SO3 + H2SO4 --> H2S2O7 
Dissolve oleum in water 
H2S2O7 + H2O --> 2H2SO4

Question 8

Step 3 of contact process equation(s)

Answer 8

SO3 + H2SO4 –> H2S2O7

H2S2O7 + H2O –> 2H2SO4

Question 9

Step 2 of the contact process equation(s)

Answer 9

2SO2 + O2 2SO3

Question 10

Step 1 of the contact process method 2 equation(s)

Answer 10

4FeS2 + 11O2 –> 2Fe2O3 + 8SO2

Question 11

Step 1 of the contact process method 1 equation(s)

Answer 11

S + O2 –> SO2

Question 12

Why is sulphuric trioxide not dissolved in water

Answer 12

Steamy fumes of sulphuric acid are produced with is dangerous and lowers the yield