- Almost all of the nitrogen in the soil is present in complex organic molecules and so is not available to plants.
- However, various processes convert the unreactive atmospheric nitrogen and organic nitrogen compounds into ammonium and nitrate ions which are available to plants.
- The main processes are shown in the nitrogen cycle below:
Useful books for revision
Revise A2 Chemistry for Salters (OCR A Level Chemistry B)
Salters (OCR) Revise A2 Chemistry