CHEM 2045C FINAL PRACTICE TEST WITH ACTUAL
COMPREHENSIVE EXAMINATION QUESTIONS AND
ANSWERS KEY PROVIDED ACADEMIC YEAR 2026-27
[Author name]
[COMPANY NAME] [Company address]
,CHEM ED EXAM
ACS
Exams 01828
ABBREVIATIONS AND SYMBOLS CONSTANTS
amount of substance n kelvin
atmosphere atm kilo —prefix AvogadroConstant Measures of pressure
= 6.02>1003mol- I atm 760 mmHg = 101.3kPa
Avogadro constant liter
Celsius temperature milli— prefix m Gas Constant
centi—prefix c molar Speed of light
8 R = 0.0821
c = 2.998x10
enthalpy H mole mol
R = 8.314
gas constant R pressure
gram second s Planck's constant
h = 6.626 x 1034 .1•s
hour h specific heat capacity
joule temperature
volunle
E UATIONS
AHr —EnAH f0 (products) —EmAfIf 0 (reactants)
P x MM
q = cmAT PV = nRT
1 PERIODIC TABLE OF THE ELEMENTS 18
1 2
I-oos 2 13 14 15 16 17 4.003
9.012 10.81 12.01 14.01 16.00 19.00 20. IS
11 12
Mg
4 5 6 7 8 9 10 11 12 26.98 2S.09 30.97 32.07 35.45 39.95
52.00 54.94 55.85 58.93 58.69 63.55 65.39 69.72 72.61 74.92 79.90
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, 1. The volume of a sample of a metal was determined using the water displacement method. The results of
3 trials were 16.72 mL, 16.79 mL and 16.69 mL.If the actual volume of the sample is 14.50 mL, the
experimental results are
A. Accurate and precise
B. Accurate and imprecise
C. Inaccurate and precise
D. Inaccurate and imprecise
2. Which of the following is not a physical change?
A. Cutting a piece of paper in half
B. Citric acid dissolving in water
C. Tarnishing of silver
D. Diffusion of a gas
3. In which of the following pairs of symbols the number of neutrons is the same?
66
I. Zn and 64Zn
66
II. Zn and 63Co
32
III. P and 29Al
A. I only
B. II only
C. III only
D. I and II
E. II and III
4. What is the mass of the compound C8H18 (Mm = 114.26 g.mol-1) that contains 7.20x1022 hydrogen
atoms?
A. 13.7 g
B. 6.07 g
C. 2.75 g
D. 0.759 g
5. Element silver has two stable isotopes, Ag-107, 106.91 amu, 51.84% and Ag-109, 108.90 amu, 48.46%.
What is its average atomic mass?
A. 107.8 amu
B. 108.2 amu
C. 107.9 amu
D. 108.4 amu
COMPREHENSIVE EXAMINATION QUESTIONS AND
ANSWERS KEY PROVIDED ACADEMIC YEAR 2026-27
[Author name]
[COMPANY NAME] [Company address]
,CHEM ED EXAM
ACS
Exams 01828
ABBREVIATIONS AND SYMBOLS CONSTANTS
amount of substance n kelvin
atmosphere atm kilo —prefix AvogadroConstant Measures of pressure
= 6.02>1003mol- I atm 760 mmHg = 101.3kPa
Avogadro constant liter
Celsius temperature milli— prefix m Gas Constant
centi—prefix c molar Speed of light
8 R = 0.0821
c = 2.998x10
enthalpy H mole mol
R = 8.314
gas constant R pressure
gram second s Planck's constant
h = 6.626 x 1034 .1•s
hour h specific heat capacity
joule temperature
volunle
E UATIONS
AHr —EnAH f0 (products) —EmAfIf 0 (reactants)
P x MM
q = cmAT PV = nRT
1 PERIODIC TABLE OF THE ELEMENTS 18
1 2
I-oos 2 13 14 15 16 17 4.003
9.012 10.81 12.01 14.01 16.00 19.00 20. IS
11 12
Mg
4 5 6 7 8 9 10 11 12 26.98 2S.09 30.97 32.07 35.45 39.95
52.00 54.94 55.85 58.93 58.69 63.55 65.39 69.72 72.61 74.92 79.90
Page 2 messages.pdf_cover_qr_code_label
C)ACS DivCHED, Examinations Institute
messages.downloaded_by
, 1. The volume of a sample of a metal was determined using the water displacement method. The results of
3 trials were 16.72 mL, 16.79 mL and 16.69 mL.If the actual volume of the sample is 14.50 mL, the
experimental results are
A. Accurate and precise
B. Accurate and imprecise
C. Inaccurate and precise
D. Inaccurate and imprecise
2. Which of the following is not a physical change?
A. Cutting a piece of paper in half
B. Citric acid dissolving in water
C. Tarnishing of silver
D. Diffusion of a gas
3. In which of the following pairs of symbols the number of neutrons is the same?
66
I. Zn and 64Zn
66
II. Zn and 63Co
32
III. P and 29Al
A. I only
B. II only
C. III only
D. I and II
E. II and III
4. What is the mass of the compound C8H18 (Mm = 114.26 g.mol-1) that contains 7.20x1022 hydrogen
atoms?
A. 13.7 g
B. 6.07 g
C. 2.75 g
D. 0.759 g
5. Element silver has two stable isotopes, Ag-107, 106.91 amu, 51.84% and Ag-109, 108.90 amu, 48.46%.
What is its average atomic mass?
A. 107.8 amu
B. 108.2 amu
C. 107.9 amu
D. 108.4 amu
