Why are combustion reactions generally exothermic?
A) Hydrogen easily pulls electrons from the oxygen in water molecules and are reduced.
B) During combustion oxygen is oxidized, which gives off lots of energy.
C) Combustion involves the transfer of electrons to oxygen, which has an extremely high tendency for gaining electrons.
D) It is highly exothermic because combustion involves an oxidation-reduction reaction between a metallic material and oxygen.
Answer: C
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