Question

Pyrite FeS2 is an ore that is used to produce sulfuric acid. During the frying of pyrite (interaction with oxygen at high temperature), sulfur dioxide is produced. This gas is also produced when coal is burned. Sulfur dioxide is one of the causes of acid rain. To reduce its emissions into the air, filters are used that contain calcium oxide or calcium dihydroxide. In the presence of catalysts and oxygen, sulfur dioxide is converted into sulfur trioxide, which dissolves in water. A chemical reaction takes place in which sulfuric acid is produced and a large amount of heat is released.

Mark the described properties of sulfur oxides with chemical equations. Where necessary, identify the oxidizing agent and reducing agent.​

Answer 1

Sulfur dioxide (SO2) properties:

Produced during the burning of pyrite and coal.
One of the causes of acid rain.
Reacts with calcium oxide or calcium dihydroxide filters to reduce emissions.
Can be converted into sulfur trioxide (SO3) in the presence of catalysts and oxygen.
Chemical equation for the oxidation of pyrite to produce sulfur dioxide:
FeS2 + 3O2 → FeO + 2SO2

Oxidizing agent: O2
Reducing agent: FeS2

Chemical equation for the conversion of sulfur dioxide to sulfur trioxide:
2SO2 + O2 → 2SO3

Oxidizing agent: O2
Reducing agent: SO2

Chemical equation for the production of sulfuric acid from sulfur trioxide:
SO3 + H2O → H2SO4

No oxidizing or reducing agent involved in this reaction.