Why is the combustion of methanol an exothermic reaction?
The breaking of bonds REQUIRES energy; the making of bonds RELEASES energy.
Now we represent the combustion of methanol as:
Now, clearly, we have to break
Certainly, we can look up standard tables of bond enthalpies (which can be derived experimentally, and also theoretically from first principles), and certainly, the value we get from these tables are identical to the actual values, i.e. the values obtained by experiment, i.e.
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