CHEM 121 FINAL – QUESTIONS AND ANSWERS | ACCURATE AND
WELL DETAILED | COMPLETE GUIDE & RATIONALES | A+
MATERIAL | NEWEST UPDATE
CORE DOMAINS *
Atomic Structure and Periodic Trends*
Chemical Bonding and Molecular Geometry*
Stoichiometry and Chemical Reactions*
Thermochemistry and Calorimetry*
Gas Laws and Kinetic Molecular Theory*
Intermolecular Forces and Solutions*
Chemical Equilibrium and Kinetics*
Acids, Bases, and Aqueous Equilibria*
INTRODUCTION *
The purpose of this comprehensive examination is to rigorously evaluate
the student's mastery of fundamental general chemistry principles and
their practical applications. This assessment measures critical thinking,
quantitative problem-solving skills, and the ability to apply chemical
theories to laboratory and real-world scenarios. Featuring a robust
structure of multiple-choice and complex scenario-based questions, the
exam emphasizes analytical decision-making, safety compliance, and the
interpretation of chemical data in professional and scientific contexts.
Students are expected to demonstrate deep conceptual understanding
rather than rote memorization, ensuring readiness for advanced scientific
coursework and professional practice.
SECTION 1: QUESTIONS 1 - 25
Question 1
What is the mass percent of carbon in glucose (C6H12O6)?
, A. 39.99%
🟢 B. 40.00%
C. 42.11%
D. 53.28%
🔴 Explanation: The molar mass of C6H12O6 is approximately (6 *
12.011) + (12 * 1.008) + (6 * 15.999) = 180.16 g/mol. The total mass of
carbon is 6 * 12.011 = 72.066 g. Dividing 72.066 by 180.16 and
multiplying by 100 yields 40.00%.
Question 2
A sample of an ideal gas occupies 4.50 L at 300. K and 1.20 atm. What is
the new volume if the pressure is increased to 3.60 atm while the
temperature remains constant?
A. 1.00 L
B. 2.25 L
🟢 C. 1.50 L
D. 3.00 L
🔴 Explanation: According to Boyle's Law (P1V1 = P2V2), temperature is
constant, so pressure and volume are inversely proportional. (1.20 atm) *
(4.50 L) = (3.60 atm) * V2, which solves to V2 = 1.50 L.
Question 3
Which of the following electron configurations represents an excited state
of a neutral atom?
A. 1s2 2s2 2p6
B. 1s2 2s2 2p5 3s1
C. 1s2 2s2 2p6 3s2
D. 1s2 2s2 2p6 3s2 3p1
🟢 B. 1s2 2s2 2p5 3s1
🔴 Explanation: In the ground state configuration of neon (10 electrons),
the electrons fill the lowest available energy orbitals: 1s2 2s2 2p6.
Promoting an electron from the 2p orbital to the 3s orbital results in 1s2
2s2 2p5 3s1, which is higher in energy and represents an excited state.
Question 4
What is the molecular geometry of sulfur hexafluoride (SF6) according to
VSEPR theory?
A. Trigonal bipyramidal
B. Square planar
🟢 C. Octahedral
D. T-shaped
🔴 Explanation: Sulfur in SF6 has six bonding pairs and zero lone pairs
around the central atom, corresponding to an octahedral electron-pair
WELL DETAILED | COMPLETE GUIDE & RATIONALES | A+
MATERIAL | NEWEST UPDATE
CORE DOMAINS *
Atomic Structure and Periodic Trends*
Chemical Bonding and Molecular Geometry*
Stoichiometry and Chemical Reactions*
Thermochemistry and Calorimetry*
Gas Laws and Kinetic Molecular Theory*
Intermolecular Forces and Solutions*
Chemical Equilibrium and Kinetics*
Acids, Bases, and Aqueous Equilibria*
INTRODUCTION *
The purpose of this comprehensive examination is to rigorously evaluate
the student's mastery of fundamental general chemistry principles and
their practical applications. This assessment measures critical thinking,
quantitative problem-solving skills, and the ability to apply chemical
theories to laboratory and real-world scenarios. Featuring a robust
structure of multiple-choice and complex scenario-based questions, the
exam emphasizes analytical decision-making, safety compliance, and the
interpretation of chemical data in professional and scientific contexts.
Students are expected to demonstrate deep conceptual understanding
rather than rote memorization, ensuring readiness for advanced scientific
coursework and professional practice.
SECTION 1: QUESTIONS 1 - 25
Question 1
What is the mass percent of carbon in glucose (C6H12O6)?
, A. 39.99%
🟢 B. 40.00%
C. 42.11%
D. 53.28%
🔴 Explanation: The molar mass of C6H12O6 is approximately (6 *
12.011) + (12 * 1.008) + (6 * 15.999) = 180.16 g/mol. The total mass of
carbon is 6 * 12.011 = 72.066 g. Dividing 72.066 by 180.16 and
multiplying by 100 yields 40.00%.
Question 2
A sample of an ideal gas occupies 4.50 L at 300. K and 1.20 atm. What is
the new volume if the pressure is increased to 3.60 atm while the
temperature remains constant?
A. 1.00 L
B. 2.25 L
🟢 C. 1.50 L
D. 3.00 L
🔴 Explanation: According to Boyle's Law (P1V1 = P2V2), temperature is
constant, so pressure and volume are inversely proportional. (1.20 atm) *
(4.50 L) = (3.60 atm) * V2, which solves to V2 = 1.50 L.
Question 3
Which of the following electron configurations represents an excited state
of a neutral atom?
A. 1s2 2s2 2p6
B. 1s2 2s2 2p5 3s1
C. 1s2 2s2 2p6 3s2
D. 1s2 2s2 2p6 3s2 3p1
🟢 B. 1s2 2s2 2p5 3s1
🔴 Explanation: In the ground state configuration of neon (10 electrons),
the electrons fill the lowest available energy orbitals: 1s2 2s2 2p6.
Promoting an electron from the 2p orbital to the 3s orbital results in 1s2
2s2 2p5 3s1, which is higher in energy and represents an excited state.
Question 4
What is the molecular geometry of sulfur hexafluoride (SF6) according to
VSEPR theory?
A. Trigonal bipyramidal
B. Square planar
🟢 C. Octahedral
D. T-shaped
🔴 Explanation: Sulfur in SF6 has six bonding pairs and zero lone pairs
around the central atom, corresponding to an octahedral electron-pair
