Transcript Stoichiometry Review - Mrs. Sasin's Chemistry Class

Stoichiometry Warmup
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I have 1 mole of CO2 gas at STP.
How many grams of CO2 do I have?
How many Liters of CO2 do I have?
How many molecules of CO2 do I have?
Stoichiometry
• The relationship between
reactants and products in a
balanced chemical equation
• Mole Ratios
Stoichiometry
• If you know the moles of a
substance, the balanced
equation allows you to
determine the moles of all other
substances in the rxn
Stoichiometry
• Coefficients from balanced
equations can be used to write
conversion factors called mole
ratios
Stoichiometry
• Write a balanced equation for
the following rxn:
• Hydrogen + nitrogen 
ammonia
Stoichiometry
• How many moles of ammonia
are produced when 0.60 mol of
nitrogen reacts with hydrogen?
Stoichiometry
• How many moles of hydrogen
gas are needed to react with
0.60 mol of nitrogen gas?
Stoichiometry
• How many grams of ammonia
are produced by the reaction of
5.40g of hydrogen with excess
nitrogen?
Stoichiometry
• How many grams of nitrogen
are needed to react with 5.40g
of hydrogen?
Stoichiometry
Stoichiometry
• How many molecules of
oxygen are produced when
29.2g of water are decomposed?
Limiting vs. Excess Reagents
• Limiting Reagent =The reactant
that determines the amount of
product formed in a rxn.
• Completely consumed in the
rxn.
Limiting vs. Excess Reagents
• Excess Reagent = the reactant
that is not completely used up
Limiting vs. Excess Reagents
• If you have 6.70 mole of Na and
3.20 mol Cl2, which is the LR?
• How many moles of NaCl is
produced?
• How many moles of ER remain?
Limiting vs. Excess Reagents
• What is the limiting reagent when
80.0g Cu reacts with 25.0g S?
• What is the maximum amount of
Cu2S in grams that can be formed?
• How many grams of ER remain?
LR video
• http://educationportal.com/academy/lesson/limitingreactants-calculating-excessreactants.html#lesson
Yield Video
• http://educationportal.com/academy/lesson/calculatingreaction-yield-and-percentage-yield-from-alimiting-reactant.html#lesson
Theoretical Yield
• Theoretical Yield = maximum
amount of product that can be
formed from given amounts of
reactants
• (based on calculation from the
LR)
Actual Yield
• Actual Yield = the amount of
product formed when the rxn is
carried out in the lab
• Based on experimentation
Percent Yield
• Percent Yield =
• actual yield / theoretical yield
• x 100
Percent Yield
• What is the percent yield of
CaO when 24.8g of CaCO3 is
heated and 13.1g CaO is
produced in the lab?
• CaCO3  CaO + CO2
Stoichiometry Review
What is the LR?
• 4 moles of oxygen gas react
with 16 moles of H2 gas.What
is the LR?
• What is the theoretical
yield of product?
What is the percent yield?
• The burning of 18.0g of
carbon in oxygen produces
55.0g of carbon dioxide.
Review Question
• Write a balanced equation for
the reaction that occurs when
Magnesium metal reacts with
Hydrochloric acid.
Review Question
• If 10.0g of Magnesium is mixed
with 35.0g of Hydrochloric
acid, what is the LR?
Review Question
• What is the theoretical yield
of magnesium chloride?
Review Question
• What is the percent yield of
Magnesium chloride if 35.0g
is produced in the lab?
Review Question
• How much excess reagent
remains?