nitrogen and fertilisers

nitrogen, phosphorus, potassium

• needed to make amino acids which are then needed to make proteins. This promote healthy leaves • ammonium ions, NH4+ and nitrate ions, NO-3, are sources of soluble nitrogen

• promotes healthy roots - phosphate ions, PO4 3- are a source of soluble phosphorus

• promotes growth and healthy fruits and flowers - most common potassium compounds dissolve in water to produce potassium ions K+

ammonia can be displaced from its salts by the addition of an alkali substance or adding a base

manufacture of ammonia

N2 + 3H2 <=> 2NH3

• forward reaction exothermic • temperature of about 450 degrees celsius: Lower temperature would favour yield but the rate of reaction would be to slow. Thus, at 450 deg celc, the rate and yield is economic • pressure of about 200atm: higher temperature would favour yield and rate but its dangerous and expensive to maintain such a high pressure system • catalyst is iron

• cracking of alkanes • steam reforming of methane • electrolysis of water

fractional distillation of air