fertilisers Flashcards
What are the essential elements in fertilisers?
Nitrogen (N)
Phosphorus (P)
Potassium (K)
What is a fertiliser?
A fertiliser is a substance which restores elements to the soil.
What are the main compounds in fertilisers that provide the essential elements?
Ammonium Salts (NH4 Cl)
Potassium Salts
Nitrates
Phosphates
How do you make ammonia in the lab?
React any ammonium salt with any alkali.
KOH + NH4 Cl ——-> KCl + H20 + NH3
What is the Haber process?
The production of ammonia by reacting nitrogen and hydrogen.
What are the conditions for the Haber process?
Iron catalyst
High pressure
Moderate temperature
What’s the equation for the Haber process?
N2(g) + 3H2(g) <——-> 2NH3(g)
What is the Otswald process?
This is the catalytic oxidation of ammonia to produce nitric acid requiring a platinum catalyst.
How do you make synthetic fertilisers by neutralisation?
Fertilisers can be made by neutralisation using the appropriate base and acid. The salt produced is the fertiliser.
e.g.
NH4 OH + HNO3(aq) —–> NH4 NO3 + H2O