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.
Barium fluoride (BaF2) - Also known as Barium(II) fluoride - because it's a combination of two different kinds of ions (binary = two).
the answer of these question is weight