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FertilisersFertilisers

There are two types of fertilisers: natural which is made from plant and animal waste, and artificial which is man-made. By using fertilisers, farmers are able to grow more crops on a field.

Part of ChemistryChemistry in society

Fertilisers

Chemistry is extremely important to the future of food production. As the population of the world increases, more efficient ways of producing foods are required. Chemists are able to help by researching which chemicals can boost plant production.

Plants require chemical nutrients from the soil in order to have healthy growth. Three of the elements found in essential nutrient compounds are:

  • nitrogen (N)
  • phosphorus (P)
  • potassium (K)

As plants grow, their roots extract nutrients from the soil and this means that as time goes on the level of nutrients present decreases.

The next year, plants growing in the same place would have insufficient nutrients to grow healthily. Different plants require different levels of each nutrient.

Both natural and synthetic fertilisers can be used to deliver the essential nutrients to the soil.

Natural fertilisersSynthetic fertilisers
Decay of dead plants and animalsHaber Process - making ammonia from nitrogen and hydrogen
Decay of plant and animal wasteOstwald Process - oxidising ammonia to make nitric acid
Natural fertilisersDecay of dead plants and animals
Synthetic fertilisersHaber Process - making ammonia from nitrogen and hydrogen
Natural fertilisersDecay of plant and animal waste
Synthetic fertilisersOstwald Process - oxidising ammonia to make nitric acid

Unfortunately soluble fertilisers can be washed away by rainwater into rivers and lakes. This causes pollution resulting in fish dying and algal blooms (a green coating) covering water.

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