Refer to the (unbalanced) equation CS₂ + CaO $\rarr$ CO₂ + CaS. How many grams of CaO are required to react completely with 38 g of CS₂

Question

Quizplus · Accepted Answer

The molar mass of CS2 is 76 g/mol, so 38 g of CS2 is 0.5 mol. The balanced equation is CS2 + 3CaO → CO2 + 2CaS, so 0.5 mol of CS2 requires 1.5 mol of CaO. The molar mass of CaO is 56 g/mol, so 1.5 mol of CaO is 84 g. However, the balanced equation should be CS2 + 2CaO → CO2 + 2CaS, which requires 1 mol of CaO per mol of CS2, so 0.5 mol of CS2 requires 0.5 mol of CaO, which is 28 g. The correct answer is not listed, so the closest is 56 g, which is incorrect.

Refer to the (Unbalanced) Equation CS2 + CaO →\rarr→ CO2 + CaS

Refer to the (Unbalanced) Equation CS₂ + CaO $\rarr$ CO₂ + CaS