Re: [Phys-L] Energy & Bonds

[John Denker <jsd@av8n.com>]

On 11/14/2013 01:09 PM, rjensen@ualberta.ca wrote:
> Does the decreased mass account for the exact binding energy (498
> kJ/mol; 5.16 eV)? or are other factors at play?

Yes, it's exact ... unless I'm misunderstanding the question.
The E=mc^2 formula doesn't leave much wiggle room.

> I can find masses of atomic isotopes, but not molecular entities.
> References to this information would be appreciates so I can do the
> above calculation.

For chemistry, the mass deficit is too small to be interesting,
so nobody bothers to measure it, let alone tabulate it.

AFAICT it has never been measured.  It looks like it's right on
the threshold of being measurable, if somebody wanted to devote
a lot of effort to it.  So I would be interested but not the
least bit surprised by news that somebody had measured such a 
thing.