NPK fertilisers Flashcards
1
Q
What is a fertiliser?
A
- A substance that is applied to soil in order to supply plants with nutrients
2
Q
What is a formulation?
A
- A mixture that has been designed to do something useful
3
Q
What is a formulated fertiliser?
A
- A fertiliser made by mixing certain chemicals in a specific ratio
4
Q
What are the main components of NPK fertilisers?
A
- Nitrogen
- Phosphorus
- Potassium
5
Q
How is ammonia used in NPK fertilisers?
A
- Ammonia reacts with oxygen and water to produce nitric acid, which is used as a source of the nitrate ions in NPK fertilisers
- Ammonia reacts with acids to form ammonium salts, which is a component in many fertilisers
6
Q
Why do plants need nitrogen?
A
- Needed to make amino acids which are used to make proteins
- Proteins needed for growth
7
Q
How do we produce phosphorus for NPK fertilisers?
A
- Phosphate is mined from the ground as phosphate rock
- As phosphate salts in the rock are insoluble, they can’t directly be used as fertilisers
- Instead, we react phosphate rocks with acids to form soluble salts
8
Q
Phosphate rocks + nitric acid
A
= phosphoric acid + calcium nitrate
9
Q
Phosphate rocks + sulfuric acid
A
= calcium sulfate + calcium phosphate
10
Q
Phosphate rocks + phosphoric acid
A
= calcium phosphate
11
Q
How do we produce potassium for NPK fertilisers?
A
- Mined from the ground and used directly in fertilisers
