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SCH3U Final Exam

2025
Exam set for 2 hrs.

Name :
Teacher :
School :
Mark :______________/64______

Instructions to students:

1. This examination booklet is 4 pages long.

Please check that you have all the pages.

2. Answer all questions with complete solutions in the spaces

provided on the examination paper.

3. You may use any school-approved calculator on this

examination. Make sure that your calculator is in DEGREE
mode.
Do not share your calculator.

4. There is a formula sheet that goes with the examination.

Exam Breakdown:
PART A KNOWLDEGE AND UNDERSTANDING
15 Page 2-3
Multiple Choice

PART B COMMUNICATION
10 Page 3
Essay

PART C APPLICATION
21 Page 3
Short Answer

PART D THINKING & INQUIRY+BONUS 16+6 Page 4

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Part A

Multiple Choice
Identify the choice that best completes the statement or answers the question.

____ 1. Which of the following matches of group number and common name is incorrect?
a Group 7 - transition metals d Group 2 - actinides
. .
b Group 2 - alkali earth metals e Group 18 - noble gases
. .
c Group 17 - halogens
.
____ 2. A nonmetal in Period 6 is
a astatine d radon
. .
b iodine e rubidium
. .
c polonium
.
____ 3. When elements are arranged in order of increasing atomic mass, their chemical properties repeat at regular
intervals. This statement is the definition of
a atomic mass d law of constant composition
. .
b periodic law e law of conservation of mass
. .
c limitations of the periodic table
.
____ 4. Why does electron affinity increase from bottom to top in a chemical family?
a Nuclear charge increases from bottom to top in a chemical family.
.
b Nuclear charge decreases from bottom to top in a chemical family.
.
c The number of energy levels increases from bottom to top in a chemical family.
.
d The number of energy levels decreases from bottom to top in a chemical family.
.
e The number of electrons increases from bottom to top in a chemical family.
.
____ 5. Which of the following is an example of a synthesis reaction?

a. Sulfur dioxide + oxygen 🡪 sulfur trioxide

b. AB 🡪 A + B
c. CH4 + 2O2 🡪 CO2 + 2H2O
d. AY + BX 🡪 AX + BY

____ 6. Which element has a complete octet?

a. Na
b. Al
c. Ne
d. C

____ 7. The concept of multiple covalent bonds is used to explain the molecular formula of
a O2 d F2
. .
b NaCl e NaOH
. .
c C2H6
.
____ 8. If XF2 is the correct formula for a metallic fluoride, then the formula for the oxide of X is
a X2O d XO2
. .
b XO e X2O2
. .
c XO4
.
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____ 9. Classify the following chemical reaction: 2AsCl3 + 3H2S → As2S3 + 6HCl
a combustion d single displacement
. .
b synthesis e double displacement
. .
c decomposition
.
____ 10. A compound was found to contain 10.06% carbon, 89.10% chlorine, and 0.84% hydrogen, by mass. If the
molar mass of the compound was found to be 119.6 g/mol, its molecular formula will be
a CHCl3 d C3H3Cl3
. .
b CH3Cl e C3HCl
. .
c CH3Cl3
.
____ 11. The limiting reagent of a chemical reaction is
a the reactant of a chemical process that is not consumed completely
.
b the product of a chemical process that is consumed completely
.
c the product of a chemical process that is not consumed completely
.
d the reactant of a chemical process that is consumed completely
.
e none of the above
.
____ 12. Sodium phosphate, Na3PO4, can be prepared by combining sodium hydroxide and hydrogen phosphate as
shown in the following balanced chemical equation:
3NaOH + H3PO4 Na3PO4 + 3H2O
If 2.5 mol of H3PO4 are reacted, the number of moles of water that will be produced is
a 1.0 d 5.0
. .
b 2.5 e 7.5
. .
c 3.0
.
____ 13. Potassium chloride and oxygen gas are formed upon heating potassium chlorate. The following balanced
equation shows this decomposition process: 2KClO3 2KCl + 3O2
The number of moles of KClO3 required to produce 5.0 mol of oxygen is
a 1.0 d 3.3
. .
b 2.0 e 5.0
. .
c 3.0
.
____ 14. Determine the number of grams of CO2 that can be produced from 48.0 g of the hydrocarbon C3H6, according
to the following equation: 2C3H6 + 9O2 6CO2 + 6H2O
a 37.6 g d 151 g
. .
b 50.2 g e 188.4 g
. .
c 87.8 g
.
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____ 15. Which of the following would NOT precipitate the CO32– ion?
a Co2+ d Ba2+
. .
b H+ e Pb2+
. .
2+
c Mg
.

Part B （10C）
Communication problem (2 MARKS EACH)
1. Explain how the number of electrons in an atom affects atomic radius.
2. Explain how first ionization energy is related to atomic radius.
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3. Element A has an atomic radius of 167 μm. Element B has an atomic radius of 66 μm. Are these two
elements most likely in the same period or same chemical family?

6. State the steps to calculate the number of moles of lead present in 8.6 × 1017 atoms of Pb.

7. Zinc oxide can be used for treating certain skin conditions. What is the molar mass of ZnO?

Part C (21A)
Application Problem (3 MARKS EACH)
86. Natural magnesium contains three isotopes: Mg-24, Mg-25, and Mg-26. In a sample, 78.70% of the atoms are
Mg-24, 10.13% of the atoms are Mg-25, and 11.17% of the atoms are Mg-26. Using a sample population of
10 000 magnesium atoms, calculate the average atomic mass of magnesium.
87. Determine the mass found in 0.77 mol of calcium hydroxide.
88. Calculate the mass of 12 ammonia (NH3) molecules.
89. What is the empirical formula of a compound whose percentage composition is found to be 69.9% iron and
30.1% oxygen?
90. A compound was found to contain 33.0% Si and 67.0% F, by mass. If the molar mass of the compound is
170.0 g/mol, calculate its molecular formula.
91. The pressure of oxygen gas inside a canister with a fixed volume is 5.55 atm at 298 K. What is the
pressure of the oxygen inside the canister if the temperature changes to 263 K? [ /3]
92. A sample of gas has a volume of 555 mL at 333 K and 746 mmHg. What is the volume of the gas if
the temperature increases to 355 K and the pressure increases to 781 mmHg? [ /3]

Part D (16+6T)
Thinking Problems
91. T.S.P. is an all-purpose cleaner that can be used to clean driveways. What volume of solution would you get
if you dissolved 150.0 g of sodium phosphate with water to produce a 0.23 mol/L solution? (4 MARKS)
94. A student wishes to precipitate all of the silver ions from 3.0 L of a 0.85 mol/L AgNO 3 solution. If the student
is aiming to precipitate silver chloride, suggest and calculate an appropriate solute concentration and volume
for a reacting solution. (4 MARKS)
74. Predict the products and write a balanced chemical equation for the following chemical reaction:
Aqueous aluminum chloride is added to a solution suspected to contain sodium carbonate. ( 2 MARKS)

75. 23.5 L nitrogen gas is consumed with excess hydrogen gas at 94.9 kPa and 273.15 K to produce
ammonia)
How many particles of nitrogen gas are consumed? [ /3]
What volume of ammonia, NH3(g), is produced? [ /3]
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BONUS. Manganese (III) fluoride, MnF3 (s), is formed by the reaction of manganese (III) iodide, MnI3 (s), with
fluoride gas. In this reaction, 1.39 g of manganese (III) iodide reacts with 25.5 g of fluorine. BONUS

2MnI3 (s) + 13 F2 (g) 🡪 2MnF3 (s) + 4IF5 (l)

How many moles of manganese (III) iodide are present? [ /1]

How many moles of fluoride gas are present? [ /1]
Which reactant is the limiting reactant? [ /2]
What mass of manganese (III) fluoride is produced? [ /1]
Which reactant is in excess? How must excess reactant remains? [ /1]

You can remove this page from the exam booklet.

Formulas and Constants
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Avogadro’s constant: 6.02 x 1023 particles

R=

1 atm = 760 mmHg = 760 torr = 101.325 kPa

SATP = 25ºC (298.15 K) and 100 kPa

STP = 0ºC (273.15 K) and 101.325 kPa (1 atm)

Use this page for your work.

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Use this page for your work.
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SCH3U-exam-review
Answer Section

MULTIPLE CHOICE

1. D*
2. A*
3. B*
4. D*
5. B*
6. C*
7. A*
8. B*
9. C
10. E
11. E*
12. A*
13. C
14. D*
15. E*
16. D*
17. D*
18. A
19. E
20. B*
21. D

SHORT ANSWER

71. The number of electrons affects the atomic radius in two ways. First, the number of populated energy levels;
the more energy levels, the larger the atomic radius. Second, the number of electrons; the more electrons
between the nucleus and the valence electrons, the more shielding occurs and the larger the atomic radius.--
COMM
72. The smaller the atomic radius, the stronger the nucleus holds its electrons and the harder it is to remove an
electron. The harder it is to remove an electron, the higher the first ionization energy.--COMM
73. same chemical family--COMM
74. 2AlCl3(aq) + 3Na2CO3(aq) Al2(CO3)3(s) + 6NaCl(aq) --THINKING
75. 2Ga2O3(s) → 4Ga(s) + 3O2(g)

76. ---COMM

77. --COMM
78. heavy metals, nitrates, and pesticides.
79. (a) In acidic solutions, [H+(aq)] > 1 × 10–7 mol/L

(b) In basic solutions, [H+(aq)] < 1 × 10–7 mol/L

80. Neutralization reactions are important in cleaning up acid spills, adjusting the pH level in swimming pools,
and in the titration of consumer products to ensure proper quality control.

81.
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82. The ozone layer is located in the stratosphere (10–50 km above Earth's surface).
83. They are readily liquefied, relatively inert, non-toxic, noncombustible, and volatile.
84. Alkanes contain only C–C single bonds, while alkynes contain one or more C–C triple bonds.
85. The numbering of the carbons in alkanes is done such that the lowest numbers are used for the branches. In
alkenes and alkynes, the location of the multiple bond takes precedence over the location of the branches.

PROBLEM

86. Mg-24: 78.70% or 7 870 atoms

Mg-25: 10.13% or 1 013 atoms
Mg-26: 11.17% or 1 117 atoms

The average atomic mass of magnesium is 24.33 u.

87. n = 0.77 mol
M = 74.1 g/mol

The mass of 0.77 mol of Ca(OH)2 is 57 g.

88.

Note: There are 6.02 × 1023 molecules of ammonia in one mole of ammonia.

The mass of one ammonia molecule is 2.83 × 10–23 g.

The mass of 12 ammonia molecules is 3.40 × 10–22 g.

89.
mFe = 69.9% × 100.0 g Fe = 69.9 g
MFe = 55.8 g/mol

mO = 30.1% × 100.0 g O = 30.1 g

MO = 16.00 g/mol

The molar ratio for Fe:O is 1.25:1.88. Dividing by 1.25 to obtain the lowest ratio, we obtain the molar ratio of
Fe:O to be 1:1.5. Multiplying this ratio by 2, we obtain a final 2:3 ratio.
The empirical formula of the compound is Fe2O3.
90.
mSi = 33.0% × 100.0 g Si = 33.0 g
MSi = 28.1 g/mol

mF = 67.0% × 100.0 g F = 67.0 g

MF = 19.0 g/mol
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The molar ratio for Si:F is 1.17:3.53. Dividing by 1.17 to obtain the lowest ratio, we obtain the molar ratio of
1:3. The empirical formula of the compound is SiF3.

The molecular formula of the compound is Si2F6.

91.

The volume of the solution will be 4.0 L.

92.

The concentration of sodium and potassium ions are 1.2 × 102 ppm and 1.4 × 102 ppm, respectively.

93.
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The concentration upon mixing the nitric acid solutions is 2.6 mol/L.
94. AgNO3(aq) + KCl(aq) → AgCl(s) + KNO3(aq)
3.0 L v
0.85 mol/L C

Since 1 mol of silver nitrate reacts with 1 mol of potassium chloride, then 2.6 mol of potassium chloride will
be required.

An appropriate solute could be potassium chloride with a concentration of 2.6 mol/L. The student could
use a 1.0-L volume of this solution.
95. m = 3.45 g
T = 273 K
P = 101.325 kPa
R = 8.31 kPa L/mol K
V=?

Convert mass to moles of CO2:

The volume occupied by the CO2 is 1.76 L.

96.
P1 V1 T1 P2 V2 T2
1000 mm Hg 100 L 27ºC + 273 = 300 K ? 120 L 0ºC + 273 = 273 K
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The new pressure of the neon gas will be 758 mm Hg.

97.
P1 V1 T1 P2 V2 T2
101.325 kPa 10.5 L 273 K 100 kPa ? 298 K

The difference in size would be 11.6 L – 10.5 L = 1.1 L.

98.
P1 V1 T1 P2 V2 T2

3.75 × 106 L
350 kPa 15ºC + 273 = 288 K 110 kPa ? –10ºC + 273 = 263 K

376 tanks would be required to store the CH4 above ground.

99. Mg(s) + 2HCl(aq) → MgCl2 (aq) + H2 (g)

P = 100 kPa
V = 5.25 L
R = 8.31 kPa L/mol K
T = 325 K
nH2 = ?
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Therefore, 4.72 g of Mg was added to the HCl to form 5.25 L of H2.

100. NH4NO2 (s) → N2 (g) + 2H2O(l)

P = 275 kPa
T = 425 K

Convert kg to g:

The volume of N2 will be 1.45 × 103 L.

ESSAY

101. -Observations and experiments were done on all of the known elements.
-Elements were arranged left to right from lightest to heaviest.
-Elements with similar physical and chemical properties were arranged in columns.
-The property arrangement superseded the mass arrangement.
-Empty spaces occurred when placing an element in a specific chemical family meant leaving a "hole" behind
it in a row.
102. Pros
-It is easier for consumers to do their own research on the chemicals used in the drugs.
-It is easier for pharmacists to determine the contents of the drugs and advise the consumer or doctor.

Cons
-It might be very easy for other companies or organizations to copy the drugs.
103. -Take a sample of each solution and test with litmus paper, a conductivity meter, and a pH meter.
-Sodium chloride solution would not change the litmus paper; show high conductivity and its pH would be 7.
-Sodium carbonate solution would turn the litmus paper blue; show high conductivity and its pH would be 8.
-Sulfuric acid solution would turn the litmus paper red; show high conductivity and its pH would be 0.7.
-Hydrofluoric acid solution would turn the litmus paper red; show low conductivity and its pH would be 2.
-Potassium hydroxide solution would turn the limus paper blue; show high conductivity and its pH would be
13.
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104.
Time Pressure Volume Temperature Number of
Molecules
while inflating increases increases increases increases
immediately decreases until increases decreases slightly constant
after bursting equal with
atmospheric
pressure

Pressure is a measurement of the number of collisions on the sides of the walls. A greater number of particles
causes more collisions and, therefore, a greater pressure. Pressure decreases after bursting to equalize with the
atmospheric pressure.

The volume of gas increases due to a greater number of particles being added to the elastic balloon. After
bursting, the volume occupied by the gas increases because it is no longer being held in a closed container.

Temperature increases while inflating because there are more collisions between particles and walls. As P
increases, so does T according to Gay Lussac’s law. Charles's law also states that as volume increases, so does
temperature. As the balloon bursts the temperature drops because there is a drop in pressure. The drop in
temperature is small due to the increased volume of the gas.

If more He is added, the number of molecules is increased. Molecules are not destroyed or added when the
balloon bursts, therefore, the number of molecules is constant.
75. 6.02x10^23
47l

Bonus
Final Answers:
1. Moles of MnI₃: ( 0.00319 , \text{mol} )
2. Moles of F₂: ( 0.671 , \text{mol} )
3. Limiting reactant: MnI₃
4. Mass of MnF₃ produced: ( 0.357 , \text{g} )
5. Excess reactant: F₂, with ( 24.7 , \text{g} ) remaining