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Hydrogen

Question
CBSEENCH11006917

Describe the industrial uses of hydrogen which depend on:
(i) the heat liberated when it burns,
(ii) its ability to react with vegetable oil in the presence of catalyst,
(iii) its ability to unite with nitrogen.

Solution

(i) When hydrogen is burnt in oxygen, heat is liberated. This heat is used in cutting as well as welding of metals. The apparatus in which heat is produced is called a oxy-hydrogen torch.
(ii) When dihydrogen is passed through vegetable oil at 8-10 atmospheric pressure and a temperature of 470 K.,vanaspati ghee (solid fat) is produced. The process is called hydrogenation or hardening of oils.
Vegetable space oil space space plus space straight H subscript 2 space space space rightwards arrow from 400 space straight K to Under space pressure of space Vanaspati space ghee left parenthesis solid space fat right parenthesis
(iii) Dihydrogen combines with dinitrogen at 770 K and a pressure of 400-600 atmospheres in the presence of finely divided iron containing molybdenum, ammonia is produced. This is called Haber’s process for the manufacture of ammonia.
straight N subscript 2 left parenthesis straight g right parenthesis space plus space 3 straight H left parenthesis straight g right parenthesis space space rightwards arrow from Fe divided by Mo to 770 space straight K of space 2 NH subscript 3 left parenthesis straight g right parenthesis