Chemistry Notes
Formation of Sulphuric Acid H2SO4
The Contact Process
1. S (g) + O2 (g) -> SO2 (g)
2. -Drying and Purification
-450 Degrees Celcius
-1 atm
-Reversible process
2SO2 (g) + O2 (g) <-> 2SO3 (g)
3.-To prevent the formation of an acid mist as the reaction between water and Sulphur Trioxide is highly exothermic.
- Mixture is called Oleum
SO3 (g) + H2SO4 (l) -> H2S2O7 (l)
4. H2S2O7 (l) + H20 (l) -> 2H2SO4 (l)
Concentrated or pure Sulphuric Acid is dark and slightly oily, while dilute Sulphuric Acid is clear
Being a dibasic acid, Sulphuric Acid can form two salts- one a normal salt and the other an acid salt where one atom of the metal (or other reactant) is replaced by a hydrogen atom.
Formation of Ammonia Haber Process NH3
1.-Nitrogen is obtained from the air (78% of air is N2)
-Hydrogen is obtained from natural gas (Methane CH4)
-Iron Catalyst
-Temperature of 450 Degrees Celcius
-Pressure of 200 atmospheres
-This reaction is exothermic
N2 (g) + 3H2 (g) <-> 2NH3 (g)
Manufacture of Iron
1.Products
-Haematite (Fe2O3)
-Coke (C)
-Air
-Limestone (CaCO3)
2.Reactions
-Coke combusts at the high temperature to form Carbon Dioxide
C (s) + O2 (g) -> CO2 (g)
-Some of the Carbon Dioxide reacts agaiin with the coke to form Carbon Monoxide.
CO2 (g) + C (s) -> 2CO (g)
-The Carbon Monoxide reduces the Iron ((III) Oxide
3CO (g) + Fe2O3 (s) -> 2Fe (l) + 3CO2 (g)
-The limestone decomposes in the heat oof the furnace to form calcium oxide and carbon dioxide. This calcium oxide reacts with the acidic impurities in the iron ore such as Silicon Dioxide to form slag.
CaO (s) + SiO2 (s) -> CaSiO3 (l)
3.Results
-The slag CaSiO3, being lighter than thhe molten iron, forms on top of the layer of molten iron that sinks to the bottom of the furnace.
-Molten iron forms at the bottom of thee furnace.