Fertilisers Flashcards
1
Q
What elements do fertilisers provide plants with?
A
Nitrogen
Potassium
Phosphorus
2
Q
Fertilisers must be…
A
Soluble for plants to absorb them
3
Q
Fertilisers can be classed as either
A
Synthetic-man made by industry
Natural-such as manure compost
4
Q
Problems with fertilisers
A
- Can seep into waters and cause pollution
- can cause problems to the natural substances in the soil if they are over-used on land.
- causes algae bloom , oxygen depletion.
5
Q
What is the haber process?
A
- When nitrogen reacts with hydrogen to form ammonia
- This reaction is reversible
- ammonia is produced as a gas
- then cooled and collected as a liquid.
6
Q
What conditions produce a better yield of ammonia?
A
Temp:450degrees
Pressure: 200 atmospheric
Catalyst:iron
7
Q
What is the oswald process?
A
- Nitric acid,is produced in the Ostwald Process
- Happens when ammonia gas reacts with water and hydrogen and is is passed over a platinum catalyst at a high temperature.
8
Q
Best conditions for the ostwald process?
A
Temp:800degrees celcius
catalyst:platinum
9
Q
What is the purpose of fertilisers
A
- replace essential elements in soil which has been removed by plants
- required due to the increase in population requiring more efficient food production.
