Answer:
The balanced chemical equation is given as:

Explanation:
When magnesium metal burns in presence of oxygen it gives white color powdered compound called magnesium oxide.
The balanced chemical equation is given as:

According to reaction, 2 moles of magnesium metal when reacts with 1 mole of oxygen gas it gives 2 moles of solid magnesium oxide.
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Answer:
58.443 g/mol
Explanation:
The molar mass of NaCl is the sum of the molar masses of the individual atoms:
Na: 22.989770 g/mol
Cl: 35.453 g/mol
The total molar mass is ...
NaCl: 58.443 g/mol
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The molar mass does not depend on whether the material is in solution or in any other form.
Answer: Fire requires oxygen to burn. Water "smothers" fire and prevents it from acquiring more oxygen. Fire also requires heat, which cool water may prevent/remove.