PORTAGE LEARNING 2026
CHEM 103
Exam 1-6
Final Exam
Comprehensive examination preparation covering
all six modules: Basic Concepts, Nomenclature,
Stoichiometry, Gas Laws, Thermochemistry,
and Quantum Theory with Chemical Bonding.
150 verified A+ questions with detailed rationales.
General Chemistry
Already Graded A+ Questions and Answers
Verified Answers | 2026 Edition
100% CORRECT SOLUTIONS
,Section 1: Module 1 Exam - Basic Concepts, Measurements, Unit Conversions, and
Atomic Structure
Q1: Express 0.000452 in correct scientific notation.
A. 4.52 x 10^4
B. 4.52 x 10^-4
C. 4.52 x 10^-3 **[CORRECT]**
D. 45.2 x 10^-5
Correct Answer: C
Rationale: Move decimal 3 places right: 4.52. Since right, exponent negative: 4.52 x 10^-3. Option A has wrong sign. Option B moves 4 places.
Option D has coefficient >10.
Q2: How many significant figures in 0.007060 m?
A. 3
B. 4 **[CORRECT]**
C. 5
D. 6
Correct Answer: B
Rationale: Leading zeros never significant. Digits 7,0,6 and trailing zero count: 4 sig figs. Leading 0.00 do not count; captive zero and trailing zero
do.
Q3: Calculate 12.35 + 8.1 + 0.234 with correct sig figs.
A. 20.7 **[CORRECT]**
B. 20.68
C. 20.684
D. 21
Correct Answer: A
Rationale: Addition: limited by least decimal places. 8.1 has 1 decimal place. Sum = 20.684, rounds to 20.7 (one decimal place).
Q4: Convert 0.045 km to centimeters.
A. 45 cm
B. 450 cm
C. 4,500 cm **[CORRECT]**
D. 45,000 cm
Correct Answer: C
Rationale: 0.045 km x 1000 = 45 m; 45 m x 100 = 4,500 cm. Or: 0.045 x 10^5 = 4,500 cm.
Q5: Convert 77 F to Celsius. (C = (F-32) x 5/9)
A. 20 C
B. 25 C **[CORRECT]**
C. 30 C
D. 35 C
Correct Answer: B
Rationale: C = (77-32) x 5/9 = 45 x 5/9 = 25 C. Common error: forgetting to subtract 32 first.
Q6: Convert 350 K to Celsius.
A. 77 C **[CORRECT]**
B. 623 C
C. 23 C
D. -77 C
Correct Answer: A
Rationale: C = 350 - 273.15 = 76.85, rounds to 77 C. Common mistake: adding 273 instead of subtracting.
, Q7: Mass 19.3 g, volume 1.00 cm3. Density?
A. 18.3 g/cm3
B. 19.3 g/cm3 **[CORRECT]**
C. 20.3 g/cm3
D. 38.6 g/cm3
Correct Answer: B
Rationale: Density = 19.3/1.00 = 19.3 g/cm3. Accepted density of gold. Option D multiplies instead of divides.
Q8: 35.0 g metal in graduated cylinder: water rises 25.0 to 30.0 mL. Density?
A. 5.00 g/mL
B. 7.00 g/mL **[CORRECT]**
C. 8.75 g/mL
D. 1.17 g/mL
Correct Answer: B
Rationale: Volume = 30.0-25.0 = 5.0 mL. Density = 35.0/5.0 = 7.00 g/mL.
Q9: Density measurements: 0.998, 1.002, 0.999, 1.001 g/mL. Accepted = 0.998. Description?
A. Accurate not precise
B. Precise not accurate
C. Both accurate and precise **[CORRECT]**
D. Neither
Correct Answer: C
Rationale: Close to each other (precision) AND close to accepted value (accuracy). Both criteria met.
Q10: Potassium-39: protons, neutrons, electrons?
A. 19p, 20n, 19e **[CORRECT]**
B. 20p, 19n, 20e
C. 19p, 19n, 19e
D. 39p, 0n, 39e
Correct Answer: A
Rationale: K atomic number 19: 19 protons, 19 electrons. Mass 39: 39-19=20 neutrons.
Q11: Carbon-14 and Carbon-12 are isotopes. True statement?
A. Different protons and electrons
B. Same protons, different neutrons **[CORRECT]**
C. Same neutrons, different protons
D. Same mass number
Correct Answer: B
Rationale: Isotopes: same element (same protons), different neutrons. C-12: 6p+6n; C-14: 6p+8n.
Q12: Cl-35 (75.77%, 34.969 amu) and Cl-37 (24.23%, 36.966 amu). Average atomic mass?
A. 35.45 amu **[CORRECT]**
B. 36.00 amu
C. 35.97 amu
D. 34.50 amu
Correct Answer: A
Rationale: (0.7577 x 34.969) + (0.2423 x 36.966) = 26.50 + 8.96 = 35.46 amu. Matches periodic table.
Q13: Which element is a halogen?
A. Na
B. Ca
C. Br **[CORRECT]**
D. Fe
Correct Answer: C
Rationale: Br is Group 17 (VIIA), halogen family: F, Cl, Br, I, At. Na=alkali metal, Ca=alkaline earth, Fe=transition.
CHEM 103
Exam 1-6
Final Exam
Comprehensive examination preparation covering
all six modules: Basic Concepts, Nomenclature,
Stoichiometry, Gas Laws, Thermochemistry,
and Quantum Theory with Chemical Bonding.
150 verified A+ questions with detailed rationales.
General Chemistry
Already Graded A+ Questions and Answers
Verified Answers | 2026 Edition
100% CORRECT SOLUTIONS
,Section 1: Module 1 Exam - Basic Concepts, Measurements, Unit Conversions, and
Atomic Structure
Q1: Express 0.000452 in correct scientific notation.
A. 4.52 x 10^4
B. 4.52 x 10^-4
C. 4.52 x 10^-3 **[CORRECT]**
D. 45.2 x 10^-5
Correct Answer: C
Rationale: Move decimal 3 places right: 4.52. Since right, exponent negative: 4.52 x 10^-3. Option A has wrong sign. Option B moves 4 places.
Option D has coefficient >10.
Q2: How many significant figures in 0.007060 m?
A. 3
B. 4 **[CORRECT]**
C. 5
D. 6
Correct Answer: B
Rationale: Leading zeros never significant. Digits 7,0,6 and trailing zero count: 4 sig figs. Leading 0.00 do not count; captive zero and trailing zero
do.
Q3: Calculate 12.35 + 8.1 + 0.234 with correct sig figs.
A. 20.7 **[CORRECT]**
B. 20.68
C. 20.684
D. 21
Correct Answer: A
Rationale: Addition: limited by least decimal places. 8.1 has 1 decimal place. Sum = 20.684, rounds to 20.7 (one decimal place).
Q4: Convert 0.045 km to centimeters.
A. 45 cm
B. 450 cm
C. 4,500 cm **[CORRECT]**
D. 45,000 cm
Correct Answer: C
Rationale: 0.045 km x 1000 = 45 m; 45 m x 100 = 4,500 cm. Or: 0.045 x 10^5 = 4,500 cm.
Q5: Convert 77 F to Celsius. (C = (F-32) x 5/9)
A. 20 C
B. 25 C **[CORRECT]**
C. 30 C
D. 35 C
Correct Answer: B
Rationale: C = (77-32) x 5/9 = 45 x 5/9 = 25 C. Common error: forgetting to subtract 32 first.
Q6: Convert 350 K to Celsius.
A. 77 C **[CORRECT]**
B. 623 C
C. 23 C
D. -77 C
Correct Answer: A
Rationale: C = 350 - 273.15 = 76.85, rounds to 77 C. Common mistake: adding 273 instead of subtracting.
, Q7: Mass 19.3 g, volume 1.00 cm3. Density?
A. 18.3 g/cm3
B. 19.3 g/cm3 **[CORRECT]**
C. 20.3 g/cm3
D. 38.6 g/cm3
Correct Answer: B
Rationale: Density = 19.3/1.00 = 19.3 g/cm3. Accepted density of gold. Option D multiplies instead of divides.
Q8: 35.0 g metal in graduated cylinder: water rises 25.0 to 30.0 mL. Density?
A. 5.00 g/mL
B. 7.00 g/mL **[CORRECT]**
C. 8.75 g/mL
D. 1.17 g/mL
Correct Answer: B
Rationale: Volume = 30.0-25.0 = 5.0 mL. Density = 35.0/5.0 = 7.00 g/mL.
Q9: Density measurements: 0.998, 1.002, 0.999, 1.001 g/mL. Accepted = 0.998. Description?
A. Accurate not precise
B. Precise not accurate
C. Both accurate and precise **[CORRECT]**
D. Neither
Correct Answer: C
Rationale: Close to each other (precision) AND close to accepted value (accuracy). Both criteria met.
Q10: Potassium-39: protons, neutrons, electrons?
A. 19p, 20n, 19e **[CORRECT]**
B. 20p, 19n, 20e
C. 19p, 19n, 19e
D. 39p, 0n, 39e
Correct Answer: A
Rationale: K atomic number 19: 19 protons, 19 electrons. Mass 39: 39-19=20 neutrons.
Q11: Carbon-14 and Carbon-12 are isotopes. True statement?
A. Different protons and electrons
B. Same protons, different neutrons **[CORRECT]**
C. Same neutrons, different protons
D. Same mass number
Correct Answer: B
Rationale: Isotopes: same element (same protons), different neutrons. C-12: 6p+6n; C-14: 6p+8n.
Q12: Cl-35 (75.77%, 34.969 amu) and Cl-37 (24.23%, 36.966 amu). Average atomic mass?
A. 35.45 amu **[CORRECT]**
B. 36.00 amu
C. 35.97 amu
D. 34.50 amu
Correct Answer: A
Rationale: (0.7577 x 34.969) + (0.2423 x 36.966) = 26.50 + 8.96 = 35.46 amu. Matches periodic table.
Q13: Which element is a halogen?
A. Na
B. Ca
C. Br **[CORRECT]**
D. Fe
Correct Answer: C
Rationale: Br is Group 17 (VIIA), halogen family: F, Cl, Br, I, At. Na=alkali metal, Ca=alkaline earth, Fe=transition.
