University of Michigan CHEM130
Chemistry Final Exam With Questions
And Rationalized Answers
Topic 1: Measurements, Significant Figures, and Units
Q1. How many significant figures are in the
number 0.004050?
• A) 3
• B) 4
• C) 5
• D) 6
• E) 7
Answer: B) 4
Rationale: Leading zeros are not significant. The digits 4,
0, 5, and 0 are significant (captive zero between 4 and 5
counts; trailing zero after decimal counts).
Q2. What is the result of 12.34 + 5.6 with the correct
number of significant figures?
, • A) 17.94
• B) 17.9
• C) 18.0
• D) 17.94 (exact)
• E) 18
Answer: B) 17.9
Rationale: For addition/subtraction, the result has the
same number of decimal places as the least precise
measurement. 5.6 has one decimal place, so the answer
must have one decimal place.
Q3. Which of the following is an intensive property?
• A) Mass
• B) Volume
• C) Density
• D) Number of moles
• E) Total energy
Answer: C) Density
Rationale: Intensive properties do not depend on the
,amount of substance. Density is intensive; mass, volume,
moles, and total energy are extensive.
Q4. Convert 25.0 °C to Kelvin.
• A) 248 K
• B) 273 K
• C) 298 K
• D) 300 K
• E) 25.0 K
Answer: C) 298 K
Rationale: K = °C + 273.15 (or 273). 25.0 + 273 = 298 K.
Q5. A sample has a mass of 15.0 g and a volume of 5.0
mL. What is its density?
• A) 0.33 g/mL
• B) 3.0 g/mL
• C) 3.00 g/mL
• D) 75 g/mL
• E) 1.5 g/mL
, Answer: B) 3.0 g/mL
Rationale: Density = mass/volume = 15.0 g / 5.0 mL = 3.0
g/mL. The answer should have two significant figures.
Topic 2: Atomic Structure & Nuclear Chemistry
Q6. Which statement about atoms is TRUE?
• A) The nucleus contains most of the atom's mass and
is positively charged.
• B) Electrons are located in the nucleus.
• C) Protons and electrons have approximately the
same mass.
• D) Neutrons are positively charged.
• E) Atoms of the same element always have the same
number of neutrons.
Answer: A) The nucleus contains most of the atom's
mass and is positively charged.
Rationale: The nucleus is small, dense, positively
charged, and contains protons and neutrons (most of the
mass). Electrons orbit outside.
Chemistry Final Exam With Questions
And Rationalized Answers
Topic 1: Measurements, Significant Figures, and Units
Q1. How many significant figures are in the
number 0.004050?
• A) 3
• B) 4
• C) 5
• D) 6
• E) 7
Answer: B) 4
Rationale: Leading zeros are not significant. The digits 4,
0, 5, and 0 are significant (captive zero between 4 and 5
counts; trailing zero after decimal counts).
Q2. What is the result of 12.34 + 5.6 with the correct
number of significant figures?
, • A) 17.94
• B) 17.9
• C) 18.0
• D) 17.94 (exact)
• E) 18
Answer: B) 17.9
Rationale: For addition/subtraction, the result has the
same number of decimal places as the least precise
measurement. 5.6 has one decimal place, so the answer
must have one decimal place.
Q3. Which of the following is an intensive property?
• A) Mass
• B) Volume
• C) Density
• D) Number of moles
• E) Total energy
Answer: C) Density
Rationale: Intensive properties do not depend on the
,amount of substance. Density is intensive; mass, volume,
moles, and total energy are extensive.
Q4. Convert 25.0 °C to Kelvin.
• A) 248 K
• B) 273 K
• C) 298 K
• D) 300 K
• E) 25.0 K
Answer: C) 298 K
Rationale: K = °C + 273.15 (or 273). 25.0 + 273 = 298 K.
Q5. A sample has a mass of 15.0 g and a volume of 5.0
mL. What is its density?
• A) 0.33 g/mL
• B) 3.0 g/mL
• C) 3.00 g/mL
• D) 75 g/mL
• E) 1.5 g/mL
, Answer: B) 3.0 g/mL
Rationale: Density = mass/volume = 15.0 g / 5.0 mL = 3.0
g/mL. The answer should have two significant figures.
Topic 2: Atomic Structure & Nuclear Chemistry
Q6. Which statement about atoms is TRUE?
• A) The nucleus contains most of the atom's mass and
is positively charged.
• B) Electrons are located in the nucleus.
• C) Protons and electrons have approximately the
same mass.
• D) Neutrons are positively charged.
• E) Atoms of the same element always have the same
number of neutrons.
Answer: A) The nucleus contains most of the atom's
mass and is positively charged.
Rationale: The nucleus is small, dense, positively
charged, and contains protons and neutrons (most of the
mass). Electrons orbit outside.
