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Question
Supply of energy may be required to initiate a reaction. State the different forms with a suitable example of reactions initiated by the supply of energy.
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Solution
Different forms of energy:
(i) Heat energy: \[\ce{N2 + O2 ->[3000^{°}C] 2NO}\]
(ii) Light energy: \[\ce{H2 + Cl2 ->[Sunlight] 2HCl}\]
(iii) Electricity: \[\ce{\underset{[acidified]}{2H2O}->[Electric][Current] \underset{[cathode]}{2H2} + \underset{[anode]}{O2}}\]
(iv) Pressure: \[\ce{N2 + 3H2 <=>[Fe/450-500°C][200 atmos.pressure] 2NH3}\
(v) Catalyst: \[\ce{4HN3 + 5O2 -> [Pt./800°C] 4NO + 6H2O}\]
(vi) Sound Energy: \[\ce{\underset{[acetylene]}{C2H2}->[Sound][Energy] 2C + H2}\]
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