Answer:

Explanation:
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In this case, the only source of hydrogen is in the 6 molecules of water, therefore, the atoms of hydrogen, by applying stoichiometry with the Avogadro's number is:

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Solids have particles that stay in place and vibrate (least energy)
Liquids have enough energy to slide past each other and have no definite shape.
Gas has a lot of energy and moves freely with no certain shape or volume
HBr is the formula for hydrobromic acid