Here it says complete and balance the following equation. We have barium solid reactant when oxygen gas. All right. So we have to remember what type of structure does barium make. If we recall memory tool #1, peroxides are bananas. Barium makes peroxides when reacting with oxygen gas.
So bariums in Group 2A. So it's two plus in charge. And then remember, what's the formula for peroxide? O2^-2 this is 2+, this is 2-. They have the same numbers in their charges, so they just cancel out and what's left behind comes together. So barium peroxide would be BA,O2. It would be a solid.
If we look, our equation is also already balanced. We have one barium on each side and two oxygens on each side. So this would be our final complete imbalance chemical reaction.