You are equating mass with matter: This is an error. As cavediver has explained, mass is the measure of the energy binding the matter, not the matter itself. You compound that problem by presenting an equation for a reaction to only 2 significant figures while ignoring the release and/or absorption of energy. Please rerun the experiment to 12 significant figures and an accounting of the energy transfers and get back to us.
You are now a million miles away from where you were in space-time when you started reading this sentence.
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