Consider that calcium metal reacts with oxygen gas in the air to form calcium oxide. Suppose we react 6.17 mol calcium with 4.00 mol oxygen gas. Determine the number of moles of calcium left over after the reaction is complete.

Question

Quizplus · Accepted Answer

From the balanced chemical equation, we know that 2 mol of calcium reacts with 1 mol of oxygen gas. Therefore, the limiting reactant is oxygen gas since we only have 4.00 mol, which is not enough to react with all 6.17 mol of calcium. The balanced chemical equation also shows that for every 2 mol of calcium that reacts, 2 mol of calcium oxide is produced. Therefore, since all the oxygen gas is used up in the reaction, we will only produce 2.00 mol of calcium oxide. That leaves 6.17 mol - 2.00 mol = 4.17 mol of calcium left over unreacted.

Consider That Calcium Metal Reacts with Oxygen Gas in the Air