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Chemistry

Fertilisers

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

Healthy plants

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

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

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

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

Nitrogen Fixation

Some plants (e.g. beans, clover) have evolved to have a symbiotic relationship with bacteria trapped in root nodules in the plant root. They trap nitrogen from air and convert it to a compound. The plant can then use this as a nutrient for growth protein. The bacteria benefit from gaining food from the plant.

close up of bacteria in the root nodule of a plant root

The pea flower is one type of plant that performs nitrogen fixation, as described in this video.

Video: Leguminous plants

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Nitrifying bacteria can convert nitrogen from the atmosphere into soluble nitrogen compounds. This process is called nitrogen fixation. The equation can be written as:

N2 → NO2

Most plants and animals cannot fix nitrogen for themselves. Beans and clover are examples of plants that can replace nutrients in the soil by nitrogen fixation from their use of root nodule bacteria.

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Fireman

Class Clips

Video clip about the uses of polymers, and how polymer technology is used in fire fighting

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A picture of Mia Cadaver

Tombstone Timeout

Test out your knowledge of chemistry with Mia Cadaver's chemistry game - it's serious fun!

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