Final answer:
To determine the grams of excess reagent remaining after the reaction ceases, identify the limiting reagent using the moles and stoichiometry. Then, use the stoichiometric ratio to calculate the amount of excess reagent that reacts. Subtracting this amount from the initial amount gives the grams of excess reagent remaining.
Step-by-step explanation:
To determine how many grams of the excess reagent will remain after the reaction ceases, we need to first identify the limiting reagent in the reaction. The balanced equation for the reaction is C₆H₁₀ + 6O₂ → 6CO₂ + 5H₂O. To do this, we can compare the amount of moles of each reactant to the stoichiometric ratio in the balanced equation.
Given that there are 35.0g of C₆H₁₀ and 45.0g of O₂, we can calculate the moles of each reactant (using their molar masses) and determine which one is limiting based on the stoichiometric ratio. The reactant that produces the smaller number of moles is the limiting reagent.
Once the limiting reagent is determined, we can use the stoichiometric ratio to calculate the amount of excess reagent that reacts. Subtracting this amount from the initial amount of the excess reagent will give us the grams of excess reagent remaining after the reaction ceases.