CHEM 103 (General Chemistry) Module 1
2026 CHEM 103 (General Chemistry)
Module 1 Practice Exam 100 Questions
and Answers with Rationales
Questions 1–25 (Foundations of General Chemistry)
Note: This is an original practice exam designed to reflect the style of a typical first-module
CHEM 103 (General Chemistry) course. Exact topics may vary by institution, but Module 1
commonly covers scientific measurement, SI units, dimensional analysis, significant figures,
atomic structure, the periodic table, and introductory chemical concepts.
1. Which branch of chemistry focuses on the composition, properties, and
reactions of carbon-containing compounds?
A. Analytical Chemistry
B. Physical Chemistry
C. ✅✅ Organic Chemistry
D. Nuclear Chemistry
Answer: ✅✅ C
Rationale: Organic chemistry primarily studies compounds containing carbon, particularly those
with carbon-hydrogen bonds.
2. Which of the following is an example of a physical property?
A. Flammability
B. ✅✅ Density
C. Reactivity with oxygen
D. Corrosiveness
Answer: ✅✅ B
Rationale: Density can be measured without changing a substance's chemical identity, making it
a physical property.
, CHEM 103 (General Chemistry) Module 1
3. Which statement best describes a chemical change?
A. Ice melting into water
B. Water boiling
C. ✅✅ Iron rusting in moist air
D. Crushing aluminum foil
Answer: ✅✅ C
Rationale: Rusting forms a new substance (iron oxide), making it a chemical change.
4. Which SI unit is used to measure mass?
A. Liter
B. Newton
C. ✅✅ Kilogram (kg)
D. Meter
Answer: ✅✅ C
Rationale: The kilogram is the SI base unit for mass.
5. Convert 250 cm to meters.
A. 0.25 m
B. 0.025 m
C. ✅✅ 2.50 m
D. 25.0 m
Answer: ✅✅ C
Rationale: Since 100 cm = 1 m, 250 cm = 2.50 m.
6. Which instrument is most appropriate for accurately measuring the volume of
a liquid in a laboratory?
A. Beaker
B. Erlenmeyer flask
, CHEM 103 (General Chemistry) Module 1
C. ✅✅ Graduated cylinder
D. Watch glass
Answer: ✅✅ C
Rationale: Graduated cylinders are designed for more accurate volume measurements than
beakers or flasks.
7. How many significant figures are in 0.004560?
A. 3
B. ✅✅ 4
C. 5
D. 6
Answer: ✅✅ B
Rationale: Leading zeros are not significant; the digits 4, 5, 6, and the trailing zero after the
decimal are significant.
8. Calculate: 12.3 + 4.56 =
A. 16.8
B. ✅✅ 16.9
C. 16.86
D. 16.860
Answer: ✅✅ B
Rationale: For addition, round to the least number of decimal places (one decimal place).
9. Calculate: 4.25 × 3.1
A. 13.175
B. ✅✅ 13
C. 13.2
D. 13.18
, CHEM 103 (General Chemistry) Module 1
Answer: ✅✅ B
Rationale: Multiplication uses the fewest significant figures. The answer should have two
significant figures.
10. Which statement best describes an atom?
A. Smallest particle of a compound
B. ✅✅ Smallest unit of an element retaining its chemical properties
C. Combination of molecules
D. Charged particle only
Answer: ✅✅ B
Rationale: An atom is the smallest particle of an element that retains that element's identity.
11. Which subatomic particle has a positive charge?
A. Electron
B. Neutron
C. ✅✅ Proton
D. Photon
Answer: ✅✅ C
Rationale: Protons carry a +1 charge and reside in the nucleus.
12. Which subatomic particle has approximately the same mass as a proton but
no electrical charge?
A. Electron
B. ✅✅ Neutron
C. Positron
D. Alpha particle
Answer: ✅✅ B
Rationale: Neutrons are electrically neutral and have nearly the same mass as protons.
2026 CHEM 103 (General Chemistry)
Module 1 Practice Exam 100 Questions
and Answers with Rationales
Questions 1–25 (Foundations of General Chemistry)
Note: This is an original practice exam designed to reflect the style of a typical first-module
CHEM 103 (General Chemistry) course. Exact topics may vary by institution, but Module 1
commonly covers scientific measurement, SI units, dimensional analysis, significant figures,
atomic structure, the periodic table, and introductory chemical concepts.
1. Which branch of chemistry focuses on the composition, properties, and
reactions of carbon-containing compounds?
A. Analytical Chemistry
B. Physical Chemistry
C. ✅✅ Organic Chemistry
D. Nuclear Chemistry
Answer: ✅✅ C
Rationale: Organic chemistry primarily studies compounds containing carbon, particularly those
with carbon-hydrogen bonds.
2. Which of the following is an example of a physical property?
A. Flammability
B. ✅✅ Density
C. Reactivity with oxygen
D. Corrosiveness
Answer: ✅✅ B
Rationale: Density can be measured without changing a substance's chemical identity, making it
a physical property.
, CHEM 103 (General Chemistry) Module 1
3. Which statement best describes a chemical change?
A. Ice melting into water
B. Water boiling
C. ✅✅ Iron rusting in moist air
D. Crushing aluminum foil
Answer: ✅✅ C
Rationale: Rusting forms a new substance (iron oxide), making it a chemical change.
4. Which SI unit is used to measure mass?
A. Liter
B. Newton
C. ✅✅ Kilogram (kg)
D. Meter
Answer: ✅✅ C
Rationale: The kilogram is the SI base unit for mass.
5. Convert 250 cm to meters.
A. 0.25 m
B. 0.025 m
C. ✅✅ 2.50 m
D. 25.0 m
Answer: ✅✅ C
Rationale: Since 100 cm = 1 m, 250 cm = 2.50 m.
6. Which instrument is most appropriate for accurately measuring the volume of
a liquid in a laboratory?
A. Beaker
B. Erlenmeyer flask
, CHEM 103 (General Chemistry) Module 1
C. ✅✅ Graduated cylinder
D. Watch glass
Answer: ✅✅ C
Rationale: Graduated cylinders are designed for more accurate volume measurements than
beakers or flasks.
7. How many significant figures are in 0.004560?
A. 3
B. ✅✅ 4
C. 5
D. 6
Answer: ✅✅ B
Rationale: Leading zeros are not significant; the digits 4, 5, 6, and the trailing zero after the
decimal are significant.
8. Calculate: 12.3 + 4.56 =
A. 16.8
B. ✅✅ 16.9
C. 16.86
D. 16.860
Answer: ✅✅ B
Rationale: For addition, round to the least number of decimal places (one decimal place).
9. Calculate: 4.25 × 3.1
A. 13.175
B. ✅✅ 13
C. 13.2
D. 13.18
, CHEM 103 (General Chemistry) Module 1
Answer: ✅✅ B
Rationale: Multiplication uses the fewest significant figures. The answer should have two
significant figures.
10. Which statement best describes an atom?
A. Smallest particle of a compound
B. ✅✅ Smallest unit of an element retaining its chemical properties
C. Combination of molecules
D. Charged particle only
Answer: ✅✅ B
Rationale: An atom is the smallest particle of an element that retains that element's identity.
11. Which subatomic particle has a positive charge?
A. Electron
B. Neutron
C. ✅✅ Proton
D. Photon
Answer: ✅✅ C
Rationale: Protons carry a +1 charge and reside in the nucleus.
12. Which subatomic particle has approximately the same mass as a proton but
no electrical charge?
A. Electron
B. ✅✅ Neutron
C. Positron
D. Alpha particle
Answer: ✅✅ B
Rationale: Neutrons are electrically neutral and have nearly the same mass as protons.
