In a chemical reaction, how can you determine the excess reactant after identifying the limiting reagent?

• A. Calculate the amount of product formed by the limiting reagent and subtract from the initial amount of the excess reactant.
• B. Multiply the initial amounts of all reactants by their molar masses.
• C. Use the stoichiometric coefficients to find the ratio of reactants used.
• D. Add the initial amounts of all reactants and divide by the number of products.

Answer: (A)

Verified step by step guidance

1. Identify the limiting reagent by comparing the mole ratio of the reactants used in the balanced chemical equation to the mole ratio of the reactants available.
2. Calculate the amount of product that can be formed from the limiting reagent using stoichiometry. This involves using the balanced chemical equation to convert moles of the limiting reagent to moles of product.
3. Determine the initial amount of the excess reactant in moles. This can be done by converting the given mass of the excess reactant to moles using its molar mass.
4. Calculate the amount of the excess reactant that reacts by using the stoichiometric relationship between the limiting reagent and the excess reactant from the balanced equation.
5. Subtract the amount of the excess reactant that reacts from the initial amount of the excess reactant to find the remaining amount of the excess reactant.