Chemical Reaction Yields and Calculations

This video tutorial covers the calculation of actual, theoretical, and percent yields in chemical reactions. It explains how to balance chemical equations, identify limiting and excess reactants, and calculate percent yield and error. The tutorial includes example problems involving ethane and ethanol reactions, demonstrating the step-by-step process of determining yields and reactant quantities.

What is the formula for calculating percent yield?

• Actual yield plus theoretical yield times 100%

• Actual yield divided by theoretical yield times 100%

• Theoretical yield minus actual yield times 100%

• Theoretical yield divided by actual yield times 100%

In a combustion reaction, what are the typical products?

• Methane and water

• Oxygen and hydrogen

• Carbon monoxide and hydrogen

• Carbon dioxide and water

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

• By using the reactant with the smallest atomic number

• By finding the reactant with the lowest mole per coefficient ratio

• By finding the reactant with the highest mole per coefficient ratio

• By comparing the mass of each reactant

What is the theoretical yield in a chemical reaction?

• The difference between actual and expected product

• The amount of reactant left over

• The actual amount of product collected

• The maximum amount of product that can be formed

How is percent error calculated?

• The absolute value of the difference between theoretical and actual yield divided by theoretical yield times 100%

• The absolute value of the difference between actual and theoretical yield divided by actual yield times 100%

• The sum of theoretical and actual yield divided by theoretical yield times 100%

• The difference between theoretical and actual yield divided by actual yield times 100%

What does the excess reactant refer to in a chemical reaction?

• The reactant that remains after the reaction

• The reactant with the highest molar mass

• The reactant that is completely consumed

• The reactant that forms the most product

In the second practice problem, what is the limiting reactant?

• Carbon dioxide

• Water

• Oxygen

• Ethanol

How do you calculate the actual yield if the reaction efficiency is given?

• Multiply the theoretical yield by the percent efficiency

• Divide the theoretical yield by the percent efficiency

• Add the theoretical yield to the percent efficiency

• Subtract the percent efficiency from the theoretical yield

What is the first step in solving a chemical reaction problem involving yields?

• Identify the limiting reactant

• Write a balanced chemical equation

• Calculate the percent yield

• Determine the excess reactant

What is the relationship between percent yield and percent error?

• Percent yield plus percent error equals 100%

• Percent yield minus percent error equals 100%

• Percent yield times percent error equals 100%

• Percent yield divided by percent error equals 100%