Name:___________________________________ Date:_____________ Period:____
Review Guide Chemistry I Honors Unit 9: Stoichiometry (201415)
1. What quantity is conserved in the reaction shown below? (circle all that apply)
2 HCl + Ca(OH)2 → 2 H2O + CaCl2
atoms
molecules
moles
mass (grams)
2. The law of conservation of mass states that in a chemical reaction ...
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3. The quantities that must always be conserved in ALL chemical reactions are
__________ and _________.
4. It takes 4 eggs and 1 cup of milk to make 2 omelets. How many eggs would it take to
make 6 omelets? ____
3 NH4OH + Al(NO3)3 → 3 NH4NO3 + Al(OH)3
5. In the reaction above, what is the mole ratio of Al(NO3)3 to NH4OH ? ___ : ___
In stoichiometric problems, what is the mole ratio used to accomplish?
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Ca(OH)2 + FeCl2  CaCl2 + Fe(OH)2
148.2 g
253.5 g
222.0 g
?g
6. According to the reaction above, how many grams of Fe(OH)2 should be formed? ______ g
7. Write the formula for percent yield:
% yield =
What is the amount of substance recovered from the reaction in the lab experiment called?
____________________
What is the theoretical yield? _______________________________________________
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8.
4 Na + O2  2 Na2O
a) How many moles of sodium will react completely with 3.82 moles of oxygen (O2)?
b) How many moles of Na2O can be produced from 13.5 mol Na?
c) How many moles of O2 are needed to produce 34.7 g Na2O (61.98 g/mol)?
9.
C2H4 + 3 O2  2 CO2 + 2 H2O
a) When 0.624 mol O2 are reacted, how many moles of carbon dioxide are produced?
b) How many grams of C2H4 (28.06 g/mol) are needed to produce 3.70 moles of water?
c) How many grams of O2 are needed to react with 2.56 g C2H4 (28.06 g/mol)?
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10.
N2 + 3 F2  2 NF3
a) When 62.0 g of fluorine (F2) are reacted, how many mol NF3 (71.01 g/mol) will form?
b) How many mol N2 are needed to produce 2.85 g NF3 (71.01 g/mol)?
c) 3.54 g of nitrogen (N2) will react with how many grams of fluorine (F2)?
11.
4 NH3 + 7 O2  4 NO2 + 6 H2O
a) What mass of NO2 (46.01 g/mol) can be produced from 3.50 mol O2?
b) 13.8 g NH3 (17.04 g/mol) would be able to produce how many mol H2O?
c) How many grams of O2 are needed to produce 15.5 g H2O?
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12.
Be + 2 HCl  BeCl2 + H2
Enough Be and HCl were added to produce 10.7 grams of beryllium chloride (BeCl2), but
only 4.50 g BeCl2 was actually recovered. What is the percent yield?
13.
2 LiOH + FeCl2  2 LiCl + Fe(OH)2
a) You began this reaction with 20.0 grams of lithium hydroxide (LiOH) (23.95 g/mol).
What is the theoretical yield of lithium chloride (LiCl) (42.39 g/mol) ?
b) You actually produced 31.1 grams of LiCl. What is the percent yield?
14.
C3H8 + 5 O2  3 CO2 + 4 H2O
Propane (C3H8) is combusted with oxygen gas as shown above. If an actual yield of 6.50 g
of water product is recovered by combusting 5.00 grams of C3H8 (44.11 g/mol), what is the
percent yield of water in the reaction?
15. In a chemical reaction, the limiting reactant is the one that is _____________________
when the reaction is completed.
The other reactant is called the ____________________ because it is _______________
when the reaction is completed.
The ______________ reactant is used to determine the maximum amount of product that
can be produced.
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16. Consider the reaction in which 2 moles of reactant A are added to 3 moles of reactant B.
Which reactant is limiting?
A. reactant A
B. reactant B
C. need more information
Explain your answer: _________________________________________________________
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2 C(s) + O2(g)
2 CO(g)
17. Solid carbon reacts with oxygen gas to produce carbon monoxide gas as shown above.
Identify the limiting reactant when 3.25 mol O2 is reacted with 48.5 g C .
N2(g) + 3 H2(g)
2 NH3(g)
18. Nitrogen gas reacts with hydrogen gas to form ammonia (NH3) as shown above. What is the
theoretical yield of NH3 (17.04 g/mol) that can be formed when 10.0 g N2 is reacted with
10.0 g H2 ?
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