CHEM 219: Module 1 Exam -
Fundamentals
Matter, Measurement, and Atomic Theory
Portage Learning 2026 Mastery Guide - 500 Practice Questions
Classification of Matter
Q1: A substance that consists of only one type of atom and cannot be broken down by
chemical means is a(n):
A. Compound
B. Element
C. Homogeneous Mixture
D. Heterogeneous Mixture
Answer: B
Rationale: An element is a pure substance consisting of atoms that all have the same number of protons.
Measurements & Significant Figures
Q2: How many significant figures are in the measurement 0.004050 g?
A. 3
B. 4
C. 5
D. 6
Answer: B
Rationale: Leading zeros are never significant. Captive zeros and trailing zeros after a decimal point are significant. (4, 0,
5, 0).
Atomic Structure
Q3: An isotope of an element differs from another atom of the same element in its
number of:
A. Protons
B. Electrons
C. Neutrons
D. Photons
Answer: C
Rationale: Isotopes have the same atomic number (protons) but different mass numbers due to a different number of
neutrons.
CHEM 219 Module 1 - Page 1
,Density Calculations
Q4: If a sample has a mass of 45.0 g and a volume of 15.0 mL, what is its density?
A. 0.333 g/mL
B. 3.00 g/mL
C. 675 g/mL
D. 30.0 g/mL
Answer: B
Rationale: Density = Mass / Volume. 45..0 = 3.00 g/mL (keeping 3 significant figures).
Temperature Conversions
Q5: A temperature of 25°C is equivalent to how many Kelvin?
A. 25 K
B. 248 K
C. 298 K
D. -248 K
Answer: C
Rationale: K = °C + 273.15. 25 + 273 = 298 K.
Physical vs. Chemical Changes
Q6: Which of the following is a chemical change?
A. Melting ice
B. Dissolving sugar in water
C. Iron rusting
D. Crushing a can
Answer: C
Rationale: Rusting is an oxidation reaction that changes the chemical identity of the iron, whereas the others are physical
changes.
Classification of Matter
Q7: A substance that consists of only one type of atom and cannot be broken down by
chemical means is a(n):
A. Compound
B. Element
C. Homogeneous Mixture
D. Heterogeneous Mixture
Answer: B
Rationale: An element is a pure substance consisting of atoms that all have the same number of protons.
Measurements & Significant Figures
Q8: How many significant figures are in the measurement 0.004050 g?
A. 3
B. 4
C. 5
D. 6
Answer: B
Rationale: Leading zeros are never significant. Captive zeros and trailing zeros after a decimal point are significant. (4, 0,
5, 0).
CHEM 219 Module 1 - Page 2
,Atomic Structure
Q9: An isotope of an element differs from another atom of the same element in its
number of:
A. Protons
B. Electrons
C. Neutrons
D. Photons
Answer: C
Rationale: Isotopes have the same atomic number (protons) but different mass numbers due to a different number of
neutrons.
Density Calculations
Q10: If a sample has a mass of 45.0 g and a volume of 15.0 mL, what is its density?
A. 0.333 g/mL
B. 3.00 g/mL
C. 675 g/mL
D. 30.0 g/mL
Answer: B
Rationale: Density = Mass / Volume. 45..0 = 3.00 g/mL (keeping 3 significant figures).
Temperature Conversions
Q11: A temperature of 25°C is equivalent to how many Kelvin?
A. 25 K
B. 248 K
C. 298 K
D. -248 K
Answer: C
Rationale: K = °C + 273.15. 25 + 273 = 298 K.
Physical vs. Chemical Changes
Q12: Which of the following is a chemical change?
A. Melting ice
B. Dissolving sugar in water
C. Iron rusting
D. Crushing a can
Answer: C
Rationale: Rusting is an oxidation reaction that changes the chemical identity of the iron, whereas the others are physical
changes.
Classification of Matter
Q13: A substance that consists of only one type of atom and cannot be broken down by
chemical means is a(n):
A. Compound
B. Element
C. Homogeneous Mixture
D. Heterogeneous Mixture
Answer: B
Rationale: An element is a pure substance consisting of atoms that all have the same number of protons.
CHEM 219 Module 1 - Page 3
, Measurements & Significant Figures
Q14: How many significant figures are in the measurement 0.004050 g?
A. 3
B. 4
C. 5
D. 6
Answer: B
Rationale: Leading zeros are never significant. Captive zeros and trailing zeros after a decimal point are significant. (4, 0,
5, 0).
Atomic Structure
Q15: An isotope of an element differs from another atom of the same element in its
number of:
A. Protons
B. Electrons
C. Neutrons
D. Photons
Answer: C
Rationale: Isotopes have the same atomic number (protons) but different mass numbers due to a different number of
neutrons.
Density Calculations
Q16: If a sample has a mass of 45.0 g and a volume of 15.0 mL, what is its density?
A. 0.333 g/mL
B. 3.00 g/mL
C. 675 g/mL
D. 30.0 g/mL
Answer: B
Rationale: Density = Mass / Volume. 45..0 = 3.00 g/mL (keeping 3 significant figures).
Temperature Conversions
Q17: A temperature of 25°C is equivalent to how many Kelvin?
A. 25 K
B. 248 K
C. 298 K
D. -248 K
Answer: C
Rationale: K = °C + 273.15. 25 + 273 = 298 K.
Physical vs. Chemical Changes
Q18: Which of the following is a chemical change?
A. Melting ice
B. Dissolving sugar in water
C. Iron rusting
D. Crushing a can
Answer: C
Rationale: Rusting is an oxidation reaction that changes the chemical identity of the iron, whereas the others are physical
changes.
CHEM 219 Module 1 - Page 4
Fundamentals
Matter, Measurement, and Atomic Theory
Portage Learning 2026 Mastery Guide - 500 Practice Questions
Classification of Matter
Q1: A substance that consists of only one type of atom and cannot be broken down by
chemical means is a(n):
A. Compound
B. Element
C. Homogeneous Mixture
D. Heterogeneous Mixture
Answer: B
Rationale: An element is a pure substance consisting of atoms that all have the same number of protons.
Measurements & Significant Figures
Q2: How many significant figures are in the measurement 0.004050 g?
A. 3
B. 4
C. 5
D. 6
Answer: B
Rationale: Leading zeros are never significant. Captive zeros and trailing zeros after a decimal point are significant. (4, 0,
5, 0).
Atomic Structure
Q3: An isotope of an element differs from another atom of the same element in its
number of:
A. Protons
B. Electrons
C. Neutrons
D. Photons
Answer: C
Rationale: Isotopes have the same atomic number (protons) but different mass numbers due to a different number of
neutrons.
CHEM 219 Module 1 - Page 1
,Density Calculations
Q4: If a sample has a mass of 45.0 g and a volume of 15.0 mL, what is its density?
A. 0.333 g/mL
B. 3.00 g/mL
C. 675 g/mL
D. 30.0 g/mL
Answer: B
Rationale: Density = Mass / Volume. 45..0 = 3.00 g/mL (keeping 3 significant figures).
Temperature Conversions
Q5: A temperature of 25°C is equivalent to how many Kelvin?
A. 25 K
B. 248 K
C. 298 K
D. -248 K
Answer: C
Rationale: K = °C + 273.15. 25 + 273 = 298 K.
Physical vs. Chemical Changes
Q6: Which of the following is a chemical change?
A. Melting ice
B. Dissolving sugar in water
C. Iron rusting
D. Crushing a can
Answer: C
Rationale: Rusting is an oxidation reaction that changes the chemical identity of the iron, whereas the others are physical
changes.
Classification of Matter
Q7: A substance that consists of only one type of atom and cannot be broken down by
chemical means is a(n):
A. Compound
B. Element
C. Homogeneous Mixture
D. Heterogeneous Mixture
Answer: B
Rationale: An element is a pure substance consisting of atoms that all have the same number of protons.
Measurements & Significant Figures
Q8: How many significant figures are in the measurement 0.004050 g?
A. 3
B. 4
C. 5
D. 6
Answer: B
Rationale: Leading zeros are never significant. Captive zeros and trailing zeros after a decimal point are significant. (4, 0,
5, 0).
CHEM 219 Module 1 - Page 2
,Atomic Structure
Q9: An isotope of an element differs from another atom of the same element in its
number of:
A. Protons
B. Electrons
C. Neutrons
D. Photons
Answer: C
Rationale: Isotopes have the same atomic number (protons) but different mass numbers due to a different number of
neutrons.
Density Calculations
Q10: If a sample has a mass of 45.0 g and a volume of 15.0 mL, what is its density?
A. 0.333 g/mL
B. 3.00 g/mL
C. 675 g/mL
D. 30.0 g/mL
Answer: B
Rationale: Density = Mass / Volume. 45..0 = 3.00 g/mL (keeping 3 significant figures).
Temperature Conversions
Q11: A temperature of 25°C is equivalent to how many Kelvin?
A. 25 K
B. 248 K
C. 298 K
D. -248 K
Answer: C
Rationale: K = °C + 273.15. 25 + 273 = 298 K.
Physical vs. Chemical Changes
Q12: Which of the following is a chemical change?
A. Melting ice
B. Dissolving sugar in water
C. Iron rusting
D. Crushing a can
Answer: C
Rationale: Rusting is an oxidation reaction that changes the chemical identity of the iron, whereas the others are physical
changes.
Classification of Matter
Q13: A substance that consists of only one type of atom and cannot be broken down by
chemical means is a(n):
A. Compound
B. Element
C. Homogeneous Mixture
D. Heterogeneous Mixture
Answer: B
Rationale: An element is a pure substance consisting of atoms that all have the same number of protons.
CHEM 219 Module 1 - Page 3
, Measurements & Significant Figures
Q14: How many significant figures are in the measurement 0.004050 g?
A. 3
B. 4
C. 5
D. 6
Answer: B
Rationale: Leading zeros are never significant. Captive zeros and trailing zeros after a decimal point are significant. (4, 0,
5, 0).
Atomic Structure
Q15: An isotope of an element differs from another atom of the same element in its
number of:
A. Protons
B. Electrons
C. Neutrons
D. Photons
Answer: C
Rationale: Isotopes have the same atomic number (protons) but different mass numbers due to a different number of
neutrons.
Density Calculations
Q16: If a sample has a mass of 45.0 g and a volume of 15.0 mL, what is its density?
A. 0.333 g/mL
B. 3.00 g/mL
C. 675 g/mL
D. 30.0 g/mL
Answer: B
Rationale: Density = Mass / Volume. 45..0 = 3.00 g/mL (keeping 3 significant figures).
Temperature Conversions
Q17: A temperature of 25°C is equivalent to how many Kelvin?
A. 25 K
B. 248 K
C. 298 K
D. -248 K
Answer: C
Rationale: K = °C + 273.15. 25 + 273 = 298 K.
Physical vs. Chemical Changes
Q18: Which of the following is a chemical change?
A. Melting ice
B. Dissolving sugar in water
C. Iron rusting
D. Crushing a can
Answer: C
Rationale: Rusting is an oxidation reaction that changes the chemical identity of the iron, whereas the others are physical
changes.
CHEM 219 Module 1 - Page 4
