AP Chemistry Stoichiometry Essentials

The video tutorial introduces stoichiometry as the math of chemical reactions, focusing on mole ratios. It covers solving mole-mole and mass-mass problems using dimensional analysis, emphasizing their importance in exams. The tutorial explains limiting reactants and how to identify them, using examples like sodium chloride production. It concludes with calculating percent yield, highlighting the difference between theoretical and experimental results in a lab setting.

What is the core of every stoichiometry problem?

• Mole ratio

• Reaction rate

• Activation energy

• Chemical formula

Why is stoichiometry compared to following a recipe in cooking?

• Because it requires precise measurements

• Because it involves heating and cooling

• Because it's a creative process

• Because it involves mixing substances

In a decomposition reaction of aluminum carbonate, how many moles of carbon dioxide are produced from one mole of aluminum carbonate?

• 3 moles

• 2 moles

• 1 mole

• 4 moles

What is the purpose of using dimensional analysis in stoichiometry?

• To identify the reactants and products

• To convert between units of measurement

• To balance chemical equations

• To predict the outcome of chemical reactions

What is the molar mass of aluminum carbonate if it contains two aluminums, three carbons, and nine oxygens?

• 342 grams/mole

• 198 grams/mole

• 128 grams/mole

• 234 grams/mole

If 85.96 grams of aluminum carbonate decomposes, how is the mass of carbon dioxide produced calculated?

• By using the molar mass of carbon dioxide

• By using the mole ratio from the balanced equation

• By measuring the gas volume

• By determining the reaction rate

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

• By comparing the reaction rates

• By comparing the amount of product each reactant can produce

• By comparing the physical states of reactants

• By comparing the molar mass of reactants

What does a percent yield tell you about a chemical reaction?

• The speed of the reaction

• The efficiency of the reaction

• The temperature at which the reaction occurs

• The pressure at which the reaction occurs

In a reaction between sodium and chlorine to produce sodium chloride, what determines the theoretical production?

• The limiting reactant

• The reaction conditions

• The amount of chlorine used

• The amount of sodium used

How is percent yield calculated?

• (Actual yield / Theoretical yield) x 100

• (Products mass / Reactants mass) x 100

• (Theoretical yield / Actual yield) x 100

• (Reactants mass / Products mass) x 100