Unit 4 Review
Naming and formula writing
1) Identify the following compounds as ionic, molecular, then name them.
Formula
What kind of compound?
Name
P2O5
___I ___C
(NH4)2CO3
___I ___C
Fe(OH)3
___I ___C
2) Identify the following compounds as ionic, molecular, acid, or hydrate and write the formulas.
Name
What kind of compound?
Formula
Copper (II) Phosphate
___I ___C
Dinitrogen tetroxide
___I ___C
Boron trichloride
___I ___C
Barium chloride
___I ___C
3) Identify the cation and anion in the following compounds
a) NaCl
cation ______
anion ______
e) Al2O3
cation ______
anion ______
b) Ca3(PO4)2 cation ______
anion ______
f) NH4OH
cation ______
anion ______
c) PbSO4
cation ______
anion ______
g) H2S
cation ______
anion ______
d) Ba(HCO3)2 cation______
anion ______
h) Fe(NO3)3 cation ______
anion ______
4) Count the number of each atom in the following compounds or groups of compounds:
a) Cu(NO3)2
Cu _____
N _____
O _____
b) PbSO4
Pb _____
S
_____
O _____
c) Fe2(CO3)3
Fe _____
C _____
O _____
d) 4CaCl2
Ca _____
Cl _____
e) 3CO2 + 5H2O
C _____
H _____
O _____
f) 3Sn(SO3)2
Sn _____
S
O _____
_____
#5-10) Use a factor-label expression to solve the following problems.
5) When you weigh out 15.5 g of copper in the penny lab, how many moles of copper are you
weighing out?
6) If you need to measure out 0.20 moles of sodium chloride, how many grams should you weigh
out?
7) How many molecules of water are there in 75.0 g of water?
8) How many moles of iron atoms are 5.50x1025 Fe atoms?
9) How many grams of carbon dioxide contains 4.50x1023 molecules of CO2?
10) How many molecules of sulfur trioxide are in 4.33 moles of sulfur trioxide?
11) Calculate the % composition of each element in the following compounds
Aluminum Carbonate =
________ %Al
________ %C
________ %O
Barium Cyanide =
_______ %Ba
________ %C
________ %N
Iron (III) Hydroxide =
________ %Fe
________ %O
________ %H
Copper (II) Nitrate =
_______ %Cu
________ %N
________ %O
12) Calculate the empirical formulas of the following compounds given their percent compositions.
a) 5.926% H, 94.07% O
b) 70.057%C, 5.923%H, 23.50%O
c) 47.35%C, 10.60% H, 42.05% O
d) What acid contains 3.69%H, 37.77%P, and 58.54%O?
13) Given the following molecular formulas, give the empirical formula
a) C6H12O6
_________________
d) H2O2
__________________
b) C12H22O11
_________________
e) Ba3(PO4)2
__________________
c) C2H4Br2
_________________
f) C6H3N3O6
__________________
14) Given the following empirical formulas and molecular masses, calculate the molecular
formulas
g
mol
g
b) CH2O, 150.1
mol
g
c) CHCl3, 119.4
mol
g
d) C2H3O2, 118.1
mol
a) C2H4O, 88.1
molecular formula = ____________
molecular formula = ____________
molecular formula = ____________
molecular formula = ____________
15) If a compound has a molar mass of 88.1 g/mol and is composed of 9.15% H, 36.32% O, and
54.53% C, what is the molecular formula of the compound?
16) If a compound has a molar mass of 164.3 g/mol and is composed of 12.27% H and 87.73% C,
what is the molecular formula of the compound?
17) Given the following lab data, determine the empirical formula of the compound.
A 2.50 g sample of a hydrate containing copper, chlorine and water was measured out. It was
heated until it came to a constant mass of 1.50 g. The remaining solid was allowed to react with a
metal to produce 0.71 g of copper. The remainder of the compound was assumed to be chlorine.
a) What was the mass of water in the compound?
b) What was the number of moles of water in the compound?
c) What was the mass of copper in the compound?
d) What was the number of moles of copper in the compound?
e) What was the mass of chlorine in the compound?
f) What was the number of moles of chlorine in the compound?
Equations and Reaction Types
1) What fundamental law of chemistry requires that equations be balanced?
2)
a)
b)
c)
d)
What do the following symbols mean in a chemical equation?
D
(g)
e) ¾
¾®
(l)
f) 
(s)
g) 
(aq)
KI
h) ¾¾®
3) Fill in the table to remind you of how to recognize a type of reaction based on just the reactants.
When the Reactants Are:__________
It Means the Reaction is:__________
A hydrocarbon and oxygen
Combustion
4) Identify the diatomic elements.
5) Balance the following equations by adding coefficients. Identify the type of each reaction.
a) _____Ca(OH)2 + _____HBr  _____CaBr2 + _____H2O
Type: ____________
b) _____Mg + _____AlI3  _____MgI2 + _____Al
Type: ____________
c) _____C3H8 + _____O2  _____CO2 + _____H2O
Type: ____________
d) _____AgOH  _____Ag2O + _____H2O
Type: ____________
e) _____Cl2 + _____Fe  _____FeCl3
Type: ____________
f) _____Ba(NO3)2 + _____Al2(SO4)3  _____Al(NO3)3 + _____BaSO4 Type: ____________
6) Given the following description, write a balanced chemical equation.
a) Copper will react with bromine to make copper(I)bromide.
b) Sodium carbonate reacts with silver nitrate to make silver carbonate and sodium nitrate.
c) Cyclohexane (C6H12) burns in the presence of oxygen to give carbon dioxide and water vapor.
d) Zinc will react with lead (IV) bromide to make lead and zinc bromide.
e) Calcium carbonate decomposes to calcium oxide and a gas.
f) Hydrochloric acid reacts with magnesium hydroxide to make magnesium chloride and water.
7) Given just the reactants, identify the type of reaction and write a balanced equation.
a) _____CaCl2 + _____AgNO3 
Type: ____________
b) _____N2 + _____Mg 
Type: ____________
c) _____Zn + _____CuNO3 
Type: ____________
d) _____C5H12 + _____O2 
Type: ____________
e) _____Sr(OH)2 + _____H2SO4 
Type: ____________
f) _____Cu(OH)2 
Type: ____________
1) Given the equation for the reaction of copper (II) chloride and aluminum
3CuCl2 (aq) + 2Al(s)  2AlCl3 (aq) + 3Cu(s)
a) How many moles of CuCl2 will react with 0.54 moles of aluminum?
b) How many moles of copper would precipitate when 1.2 moles of aluminum react?
2) For the reaction of hydrochloric acid and barium hydroxide,
2HCl(aq) + Ba(OH)2 (s) BaCl2 (aq) + 2H2O(l)
a) How many moles of hydrochloric acid will react with 0.750 grams of barium hydroxide.
b) How many grams of barium hydroxide should be used to produce 3.40 moles of water?
3) For the reaction of lead (II) nitrate and potassium iodide to produce lead (II) iodide and
potassium nitrate, write a balanced equation:
a) How many grams of potassium nitrate are needed to cause 0.450 grams of lead (II) nitrate to
completely react?
5) If you are making hamburgers and you have the following ingredients:
16 buns, 24 hamburger patties, 36 pickle slices, 16 slices of cheese, and 30 strips of bacon…
How many bacon cheeseburgers can you make if each one requires 1 bun, 1 hamburger, 3 pickles, 1
slice of cheese and 3 strips of bacon?
How many pickle slices will you have left over?
Conversion factors
Grams
Grams
Moles Reactant
Moles Product
Liters
Liters
3-Step Stoichiometry
1. If needed, __________________ the equation.
2. If you are not given moles, find ____________ by _______________ the given number by the
conversion factor for the given unit.
3. ________________ by the mole ratio. The mole ratio is the ________________________ of the
product divided by the reactant.
4. ________________ by the conversion factor needed to find the unit requested for the product in the
problem.
Mg(s) +
HCl(aq)  MgCl2(aq) +
H2(g)
How many grams of magnesium chloride are formed from 4.95g of magnesium?
4.95g Mg x __________________ x ___________________x__________________ =
g MgCl2
How many grams of hydrogen gas are formed from 2.56g of magnesium?
2.56g Mg x ___________________ x ___________________ x ___________________ =
H2(g) + O2(g) 
g H2
H2O(g)
How many grams of water vapor are formed from 1.7 grams of hydrogen gas?
1.7g H2 x ___________________ x ____________________ x ___________________ =
g H2O
Limiting Reactants & Theoretical Yield
Theoretical yield is the amount of product in______________ that should ideally be formed in a reaction. To
Percent Yield
_____________________________ x 100
A ___________ percent yield is good!
Actual Yield is the amount of ________________ in grams measured at the end of an experiment and is
______________ in a word problem. Possible phrases that are given with the actual yield value include:
grams were _______________, grams were _______________, or grams _______________.
For more SOL practice online go to: http://education.jlab.org/solquiz/index.html
Click on “Chemistry” and “More options, please.” Then select “Molar Relationships”
2. Cu(s) + 2AgNO3(aq)  Cu(NO3)2(aq) + 2Ag(s) When copper reacts with silver nitrate according to the
equation, the number of grams of copper required to produce 432 grams of silver is —
A 31.5 g
B 127 g _
C 216 g
D 252 g
3. H2(g) + I2 (g)  2HI(g) Ten moles of hydrogen and ten moles of iodine were put into a sealed 1 L
container at 490C and allowed to react. After a while, there were still small amounts of unreacted
hydrogen and iodine, but the hydrogen iodide concentration became constant. This is because —
F there was not enough H to react with all of the I
H the reaction reached a state of
equilibrium
G the hydrogen iodide was reacting with the container J iodine loses its reactivity at high
temperature
6. A solution contains 225 g of glucose, C6H12O6, dissolved in enough water to make 0.825 L of
solution.
What is the molarity of the solution?
A 0.66 M
B 0.97 M
C 1.03 M
D 1.52 M
4. 2C2H6 + 7O2 → 4CO2 + 6H2O To produce 12 mol of water, how many mol of oxygen gas are
needed?
A2
B7
C9
D 14
5. The number of grams of oxygen required for the complete combustion of 4.00 g of methane (CH4) is
—
F 4.00 g
G 8.00 g
H 16.0 g _
J 32.0 g
3. Cu(s) + 2AgNO3(aq)  Cu(NO3)2(aq) + 2Ag(s) When copper reacts with silver nitrate according to the
equation, the number of grams of copper required to produce 432 grams of silver is —
A 31.5 g
B 127 g _
C 216 g
D 252 g
12. Carbon disulfide is prepared industrially by reacting carbon with sulfur dioxide according to this
equation. 5C + 2SO2  CS2 + 4CO
If 5.9 moles of carbon react, how many moles of CS2 are
produced?
F 0.077 moles
G 1.2 moles _
H 1.5 moles
J 30 moles
Check your answers:
1=
2=
8=
9=
3=
10 =
4=
11 =
5=
12 =
6=
13 =
7=