Limiting and Excess Reactants

What is a limiting reactant?

• The limiting reactant is the reactant that is formed as a product in a chemical reaction.

• The limiting reactant is the reactant that is partially consumed in a chemical reaction.

• The limiting reactant is the reactant that is completely consumed in a chemical reaction.

• The limiting reactant is the reactant that is added in excess in a chemical reaction.

How do you determine the limiting reactant in a chemical reaction?

• By observing the color change of the reactants.

• By comparing the mole ratio of reactants to the stoichiometry of the balanced equation.

• By measuring the temperature change during the reaction.

• By calculating the volume of the reactants.

What is an excess reactant?

• A reactant that is completely consumed in a reaction.

• A reactant that is present in a greater quantity than necessary for a complete reaction.

• A reactant that is not necessary for a reaction to occur.

• A reactant that is present in equal quantities to other reactants.

How do you calculate the amount of excess reactant remaining after a reaction?

• Subtract the amount of the limiting reactant that reacted from the initial amount of the excess reactant.

• Add the amount of the limiting reactant that reacted to the initial amount of the excess reactant.

• Multiply the amount of the limiting reactant that reacted by the initial amount of the excess reactant.

• Divide the amount of the limiting reactant that reacted by the initial amount of the excess reactant.

In a chemical reaction, if the amount of one reactant is insufficient to completely react with the other reactant, what is the reactant called?

• excess reactant

• catalyst

• inert reactant

• limiting reactant

What is the purpose of identifying the limiting reactant in a reaction?

• To identify the excess reactant in the reaction.

• To determine the maximum amount of product that can be formed.

• To calculate the average rate of the reaction.

• To determine the minimum amount of product that can be formed.

How do you calculate the theoretical yield of a reaction?

• Using the volume of the reactants and the molar mass of the product.

• By dividing the mass of the product by the molar mass of the limiting reactant.

• Calculating the average of the actual yields from multiple trials.

• Using stoichiometry and the mole ratio of the limiting reactant with the desired product.

What is the difference between the actual yield and the theoretical yield?

• The actual yield is the amount of product obtained in a chemical reaction, while the theoretical yield is the amount of product that should be obtained based on stoichiometry calculations.

• The theoretical yield is the amount of product obtained in a chemical reaction.

• The actual yield is always greater than the theoretical yield.

• The actual yield is the amount of product that should be obtained based on stoichiometry calculations.

How do you calculate the percent yield of a reaction?

• Actual yield / Theoretical yield * 100

• Actual yield - Theoretical yield * 100

• Actual yield * Theoretical yield / 100

• Actual yield + Theoretical yield * 100

What are some factors that can affect the percent yield of a reaction?

• Reactant concentration, temperature, pressure, catalysts, impurities, and reaction time.

• Reactant concentration, temperature, pressure, catalysts, impurities, and reaction rate.

• Reactant concentration, pH level, solvent polarity, reaction vessel size, stirring speed, and light intensity.

• Reactant volume, pH level, solvent polarity, reaction vessel size, stirring speed, and light intensity.