Answer:
37.046 grams of oxygen gas were produced.
Explanation:

Moles of potassium chlorite = 
According to reaction 2 moles of potassium chlorite gives 3 moles of oxygen gas.
Then 0.7718 moles of potassium chlorite will give:
of oxygen gas.
Mass of 1.1577 moles of oxygen gas:
1.1577 mol × 32 g/mol = 37.046 g
37.046 grams of oxygen gas were produced.
Open system is a system in which mass or energy can be lost to or gained from the environment. In this case, water and power come from external sources best explains why a washing machine would be considered an open system.
The correct answer is 12.2% BaO.
The solution is found by dividing the mass of the BaO, which is 25.8 grams, by the total mass of the solution, which is 212 grams, then multiplying it by 100 to get the percentage: