The Haber Process And NPK fertilisers Flashcards
Where are the raw materials in the Haber process sourced from?
Balanced symbol equation for haber process
Nitrogen is sourced from the air
Hydrogen is sourced from reacting methane with steam
N2 +3H2 ><2NH3
Reversible reaction
Conditions for the production of Ammonia
Temperature-400 decrees Celsius
Pressure-200 atmospheres
Catalyst-Iron in pea size lumps
Why is 450 degrees Celsius used in the Haber process ?
The forwards reaction is exothermic, so the reaction favors low temperatures, which slows down the rate of reaction. So we must compromise and use high temperatures to speed up rate of reaction for a lower yield.
Why are 200 atmospheres of pressure used in the Haber Process?
The reaction has 4 moles—>2 moles,
So the reaction favors high pressures.But high pressures and expensive to achieve and maintain(and unsafe) so we must compromise. We must use a lower pressure for a lower yield.
Describe the Haber process
Hydrogen and nitrogen enter in a 3:1 ratio, through the temperature, pressure and iron catalyst. They are then cooled by a condenser which liquefies the ammonia and it is removed. The excess hydrogen and nitrogen and recycled
How can:
Potassium chloride,potassium sulfate and phosphate rock
Be obtained?
Potassium chloride and potassium sulfate can be mined and used directly in the fertilizers because they are soluble
Phosphate rock can also be mined but is insoluble do must be treated with nitric or sulfuric acid to form soluble salts
How is nitrogen made for NPK fertilizers?
Directly from the Haber process
Reaction between
Phosphate rock+nitric acid
Phosphate rock+sulfuric acid
Phosphate rock+phosphoric acid
*Phosphate rock+ nitric acid
—>phosphoric acid + calcium nitrate
*Phosphoric rock+sulfuric acid
—> calcium phosphate+calcium sulfate
*Phosphate rock+phosphoric acid
—>calcium phosphate
