Methane is used as an alternative fuel. The combustion of methane releases carbon
dioxide and water. The balanced equation for this reaction is:
CH4(g) + O2 (g) → CO2 (g) + 2H2O (g) + 891 kJ.
mol-1
The activation energy for this reaction is 172 kJ.
mol-1.
7.1 Is this reaction ENDOTHERMIC or EXOTHERMIC? Give a reason for the
answer. (2)
7.2 Explain why all chemical reactions need activation energy. (2)
7.3 Why is this reaction not considered to be environmentally friendly? (2)
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