When 10.0 mol of calcium metal is reactec with 3.9 mol of oxygen gas how much calcium oxide is produced?

To determine how much calcium oxide (CaO) is produced, we first need to consider the balanced chemical reaction: 2 Ca + O₂ → 2 CaO. From the equation, 2 moles of calcium react with 1 mole of oxygen to produce 2 moles of calcium oxide. With 10.0 moles of calcium, it can react with 5.0 moles of oxygen, but only 3.9 moles of oxygen are available. Therefore, the limiting reactant is oxygen, producing 3.9 moles of CaO.