Answer:
3.98 g
Explanation:
Step 1. Write the balanced chemical reaction. In this case, magnesium reacts with oxygen to produce magnesium oxide:

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Step 2. Calculate the number of moles of magnesium:

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Step 3. Calculate the number of moles of oxygen:

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Step 4. Identify the limiting reactant comparing the equivalents. Equivalent of Mg:

Equivalent of oxygen:

Therefore, Mg is the limiting reactant.
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Step 5. According to the stoichiometry of this reaction:

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Step 6. Convert the number of moles of MgO into mass:

False.
Na does represent sodium, but NOT when it lost an electron. Na+ represents sdoium when it lost its electron.
I think the answer is a. and d.
hope this helps!!
The answer is C. Assume specific heat to be 4.18 J/g/C
A catalyst is a substance that speeds up a chemical reaction.