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Acids and Alkalis

Manufacture of Sulfuric Acid  -  The Contact Process.

Sulfuric acid is made using the contact process.

Sulfuric acid has many uses in industry.
The amount of sulfuric acid which a country uses in one year
can be a measure of that country's economic development
(how modern or wealthy it is).

Raw Materials to Make Sulfuric acid.

The raw materials (the things you need) are sulfur, air and water.
Sulfur is available from fossil fuels and sulfide ores.

When sulfur in fossil fuels is burned it produces sulfur dioxide gas.

This is the balanced chemical equation for the reaction of
sulfur with oxygen.

sulfur  +  oxygen      sulfur dioxide.
S_(s)  +     O_2(g)               SO_2(g)

Sulfide ores are heated in air
to produce the metal oxide and sulfur dioxide gas, for example

lead sulfide      +      oxygen      lead oxide + sulfur dioxide. 
2PbS_(s)          +        3O_2(g)         2PbO_(s)     +     2SO_2(g)

The metal is then extracted from the metal oxide.

Sulfur is oxidised in these reactions to become sulfur dioxide.
Both of the above reactions are exothermic.
The sulfur dioxide gas produced from both of the above methods
is used to make sulfur trioxide.

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