Re: chemical potential energy

On Nov 11, 4:31 pm, "CWatters" <colin.watt...@xxxxxxxxxxxxxxxxxxx>
wrote:
<hhc...@xxxxxxxxx> wrote in message

news:1194801116.036063.65320@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> In case 1, only a nearly insignificant portion of the total mass (the

chemical bonds) will be converted to energy, but the total mass after
the combustion will be actually be slightly less than previously in
precise accordance with E=MC^2.

Forgive my ignorance but wouldn't the mass of the waste products be greater
than the mass of the fuel because oxygen from the air has been added during
the burning process?

You are perfectly correct in the case of an open system, but in a
closed system the oxygen is considered one of the reactants and the
combustion products will have a slightly lower mass than the sum of
the pre-reaction components because the net reorganization of chemical
bonds has liberated energy during combusion.

In a chemical combustion process, so little mass is converted to
energy that it is difficult to measure, but I believe that such
measurements have actually been performed.

Harry C.




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