Gap-fill worksheet question Quiz "The Synthesis and Uses of Ammonia - Fertilisers"

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(1) NH3gif.gifThe important gas ammonia is made by a process called the .

(2) Ammonia is made by combining (from air) with hydrogen, from e.g. (natural gas).

(3) balance3.gifThe unbalanced reaction equation is ...
N2(g) + H2(g) ===> NH3(g)
and the formation of ammonia is exothermic.
One way of producing hydrogen is to react natural gas with water ...
the unbalanced equation is ...
CH4(g) + H2O(g) ===> CO(g) + H2(g)

(4) From the rules on chemical equilibrium and the information in (3) you can get a greater yield of ammonia by (i) the pressure and (ii) the temperature. However, in reallity, you cannot have the temperature to low or the of the reaction is too .

(5) Fertiliser1.gifOne of the most important uses of ammonia is to convert it into ammonium salts to provide the element in .

(6) For example ...
ammonia + ===> ammonium nitrate
or
ammonia + ==> ammonium sulfate.

Fertiliser3.gif The solutions can be evaporated to the salts.

(7) The use of artificial fertilisers is contraversial because it is costly () and does not produce which needs constant replenishment after each crop.

(8) Fertiliser2.gifUsing like cow dung is for soils and is the only acceptable way of . but probably cannot produce the huge quantities of food required to feed the world.