Reversible reactions :
(i) A reversible reaction is a reaction that can be reversed .
(ii ) The products can be converted back that can reactants .
(iii ) A reversible reaction is represented by a double arrow with their heads in the direction opposite to each other .
(iv ) The compound `'Ab'` undergoes decomposition to form the products 'A' and 'B'.
(v ) it is the forward reaction .
(vi) As soon as the products are formed , they combine togther to to form 'AB' . It is the backward reaction .
E.g `PCI_(5(g))hArr PCI_(3(g)) +Cl_(2(g))`
Irreversible reactions :
(i) the reaction that cannot be reversed is called irreversible reaction .
(ii) E.g Combustion of coal into carbon dioxide and water .
`underset("Coal ") underset("Oxygen ")O_(2(g)) to underset("Carbon dioxide ")CO_(2(g))+`Heat
(iii) Solid coal burns - with oxygen and gets converted into carbon dioxide gas and water .
(iv ) As soon as the gases formed , escapes out of the reaction container .
(v) It is hard to decompose a gas into a solid .
(vi ) THus , the backward reaction is not posible in this case , so it is an irrversible reaction .
