The difference between phosph
ite and phosph
ate is an oxidation state. They are likely not interchangeable, although I haven't checked you math. You could certainly try it, on a small scale, to see the difference.
Your water reaction with sodium salts to produce protons isn't a real one that I expect to happen. If you found it in a text book you should share the reference with us.
I have no idea what the vacuum chamber is supposed to do in this context.
You seem new to basic chemistry. I'm sorry if my answers aren't more helpful, but we're clad to fill in a few concepts. But everyone here, on the forums, new student, professional who needs a refresher, engineer who has lost touch with the basics or even the home chemist with a brilliant new idea is called upon, by all of us, to cover the basics on their own. That's part of the
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