CHAPTER 9 JEOPARDY
A.
De-finest Chapter in the book
I. “_________ ___________ involves the mass relationships between reactants and products
in a chemical reaction” (Reaction Stoichiometry)
II. “________ ___________ is a conversion factor that relates the amounts in moles of any
two substances involved in a chemical reaction” (Mole Ratio
)
III. When you calculate the amount of product formed in a reaction using a grams  grams
conversion, you are actually calculating the value of this term. ( Theoretical Yield )
IV. Which yield typically has a smaller numerical value: actual or theoretical? (actual
)
V. Why is #IV the case? Name at least two reasons.
VI. The substance that isn't completely used up in a reaction is the: (excess reactant
)
VII. What is the first mathematical conversion step in a mass-to-mass problem?
B.
The 17th and 18th moles on the golf course
I.
The elements lithium and oxygen combine to form lithium oxide. How many moles of
lithium oxide will form if 2.0 mol of Lithium begins the reaction? (1.0 mol Li2O)
II. Tetrachloroethylene (C2Cl4) is a dry cleaning liquid made from the reaction of Acetylene
(C2H2) and Chlorine Gas (Cl2), according to this equation:
C2H2 + 3Cl2 + Ca(OH)2 → C2Cl4 + CaCl2 + 2H2O
How many moles of Cl2 are needed to react with 4mol of C2H2? (12mol Cl2
)
III. The disinfectant Hydrogen peroxide (H2O2) decomposes to form water and oxygen gas.
How many moles of O2 will result from the decomposition of 5mol of Hydrogen peroxide?
(2.5mol O2)
IV. The decomposition of potassium chlorate requires 10 moles of KClO3 to produce 15moles
of Oxygen Gas (O2). What is the balanced reaction? (2KClO3 → 2KCl + 3O2)
C.
Come on moles, win the game, kick their mass!
In an automobile airbag, Sodium Azide (NaN3) rapidly decomposes into Nitrogen gas and
Sodium metal: 2NaN3 → 2Na + 3N2
If 0.500 moles of NaN3 react, how many grams of N2 are created? (21.0g Na )
I.
Silicon Carbide is made for drill bits via this reaction: SiO2 + 3C → SiC + 2CO
II.
How many grams of Silicon Carbide should be produced from 2.00mol of pure carbon? ProTip: While waiting for the silicon carbide to be created, don't inhale the carbon monoxide.
(26.7g SiC)
III.
Coal can be converted into methane gas via this UNBALANCED reaction:
C + H2O → CH4 + CO2
What mass of carbon is required to make 1.0 mol CH4? (24.0g Carbon)
IV. Sulfur Dioxide (SO2) is produced in Coal-based power plants. SO2 can become sulfuric acid
(as acid rain) via the following reaction:
2SO2 + O2 + 2H2O → 2H2SO4
What mass of SO2 is needed to react fully with 1200g of O2? (4805g of SO2)
D.
Mass to Mole Conversions! Dogs and Cats living together! MASS HYSTERIA!
I.
Oxygen gas was first discovered via the decomposition of Mercury Oxide, HgO:
2HgO → 2Hg + O2
How many moles of Mercury oxide are required to form 125g of Oxygen gas? (7.81mol HgO)
II.
Chlorine gas can be made via the electrolysis of table salt dissolved in water (“brine”)
(unbalanced) NaCl + H2O → NaOH + Cl2 + H2
If the brine contains 250g of table salt, how many moles of Cl2 can be produced? (2.14mol Cl2)
III.
The complex compound PtCl2(NH3)2 is an effect cancer fighting agent. Is is made via the
following equation:
K2PtCl4 + 2NH3 → 2KCl + PtCl2(NH3)2
How many moles of NH3 are needed to produce 30g of PtCl2(NH3)2? (0.200mol NH3)
E.
Mass to Mass Problems. 3 Conversions. That's it.
I.
II.
a.
(Unbalanced) Na2O2 + H2O → NaOH + O2
What mass of O2 is produced when 50.0g of Na2O2 react? (30.7g O2)
Milk of Magnesia can settle an upset stomach via the following reaction:
Mg(OH)2 + 2HCl → 2H2O + MgCl2
What mass in grams of MgCl2 will be produced from 3.00g of Mg(OH)2 ,a typical
dose? (4.90g of MgCl2)
III.
(Unbalanced) C2H2 + O2 → CO2 + H2O
How many grams of CO2 are created from 2.5x104g of Acetylene, C2H2? (8.5x104g)
F.
I.
II.
Push it to the limit!
Methanol is created via a reaction of hydrogen gas and carbon monoxide:
2H2 + CO → CH3OH
If 500 moles of CO are reacted with 750moles of H2, which is the limiting reactant? (H2
)
If 20.5g of Chlorine Gas (Cl2) react with 20.5g of Sodium Metal (Na) to produce Sodium
Chloride (NaCl), which is the excess reactant? (Sodium is in excess)
III.
Five Carbon Atoms + Ten Oxygen Molecules → Five Carbon Dioxide Molecules + Five
Oxygen Molecules. Which is the limiting reactant? (Carbon Atoms are in excess)
IV.
Aspirin is made by the reaction of Salicylic Acid (C7H6O3) and Acetic Anhydride (C4H6O3)
via this equation:
2C7H6O3 + C4H6O3 → 2C9H8O4 + H2O
When 20.0g of C7H6O3 and 20.0g of C4H6O3 react, which is the limiting reactant? (C7H6O3 is
limiting)
G.
I.
II.
Percent Yield is a really easy equation.
What is the percent yield when the actual yield is 20g and the theoretical yield is 24g?
(83.3% )
Sulfur Dioxide is produced from Zinc Sulfide via this reaction: 2ZnS + 3O2 → 2ZnO +
2SO2
a.
If the typical yield is 86.78% of the theoretical value, how much SO2 should be expected to
be made if 4897g of ZnS are used? (2794g of SO2)