U3-3 - Fertilisers Flashcards
3 elements essential to plants
P, N, K
(phosphorus, nitrogen potassium)
Which two properties must a fertiliser have?
- Soluble in water
- Contains one or more of P, N, K
What type of reactions make synthetic fertilisers?
Neutralisation reactions
What type of compounds are synthetic fertilisers?
Salts
A salt solution was made. How can a solid salt sample be produced?
Evaporation
(Boil away the solvent)
Formula for ammonia
NH3
Describe the properties of ammonia
(smell, hazards, solubility/pH)
Sharp unpleasant smell
Toxic
Dissolves in water to form alkaline solutions
This process is used to make ammonia
Haber process
This process is used to make nitric acid
Ostwald process
Name the chemical made in the Haber process
Ammonia (NH3)
Name the chemical made in the Ostwald process
Nitric acid (HNO3)
Catalyst used in the Haber process
Iron
Catalyst used in the Ostwald process
Platinum
Equation for the fomation of ammonia (from nitrogen and hydrogen)
N2 + 3H2 ⇌ 2NH3
What does ⇌ mean in equations?
Reaction is reversible (goes both ways)