CHEM 101 General Chemistry Exam Bank
2026/2027 | 150 Practice Questions with
Answers & Explanations | Study Guide for
Midterms & Finals
Description:
Master General Chemistry with this comprehensive 2026/2027 exam bank featuring 150
multiple-choice questions covering intermolecular forces, solutions, kinetics, acids and bases,
buffers, thermodynamics, electrochemistry, and nuclear chemistry. Each question includes a
detailed answer and expert explanation to reinforce your understanding of key concepts. Perfect
for university students preparing for midterms, finals, and standardized tests. This study
resource covers all major topics with practice problems, calculation examples, and concept
reviews aligned with current curriculum standards.
Download now and boost your exam performance with this essential chemistry study guide for
academic success in 2026/2027.
, CHEM 101 Exam Bank 2026/2027 – 150 Questions & Answers
PART A: STATES OF MATTER AND INTERMOLECULAR FORCES
Question 1
If a solid sample (not water) at its triple point undergoes a pressure increase of 150 torr while
temperature remains constant, in which phase will the sample exist?
A. Solid
B. Liquid
C. Gas
D. Plasma
E. Both gas and liquid properties
Answer: A. Solid
Explanation: At the triple point, all three phases coexist in equilibrium. The solid-liquid phase
boundary typically has a positive slope (for most substances except water), meaning that
increasing pressure at constant temperature favors the denser phase, which is generally the solid
phase. Therefore, the sample will transition to the solid phase.
Question 2
Which statement accurately describes the process of boiling?
A. High-energy molecules escape from the liquid, causing the average kinetic energy of the
remaining liquid to decrease
B. Molecules begin to adopt long-range order
C. Temperature continues to rise steadily as additional heat is supplied
D. The average kinetic energy of molecules in the liquid increases
E. The process is exothermic
Answer: A. High-energy molecules escape from the liquid, causing the average kinetic
energy of the remaining liquid to decrease
,Explanation: During boiling, the most energetic molecules overcome intermolecular forces and
escape into the gas phase. This selective removal of higher-energy molecules reduces the average
kinetic energy of the remaining liquid. The temperature remains constant during boiling as added
energy goes toward the phase change (enthalpy of vaporization) rather than increasing kinetic
energy.
Question 3
Based on intermolecular forces, determine the correct order of decreasing boiling points:
A. CH₄ > SnH₄ > H₂Te > H₂S > H₂O
B. H₂O > SnH₄ > H₂S > H₂Te > CH₄
C. H₂O > H₂Te > SnH₄ > H₂S > CH₄
D. H₂Te > H₂O > SnH₄ > H₂S > CH₄
E. SnH₄ > H₂S > H₂O > H₂Te > CH₄
Answer: C. H₂O > H₂Te > SnH₄ > H₂S > CH₄
Explanation: Water exhibits exceptionally strong hydrogen bonding, giving it the highest
boiling point despite its low molecular mass. For the chalcogen hydrides (H₂Te, H₂S), boiling
points generally increase with molecular mass due to stronger dispersion forces—thus H₂Te >
H₂S. SnH₄ has stronger dispersion forces than H₂S due to its larger molecular size, while CH₄ has
the lowest boiling point due to weak dispersion forces and no hydrogen bonding.
Question 4
Which sample of ethanol exhibits the greatest rate of vaporization?
A. 50 mL ethanol at 25°C in a 100 mL beaker (4 cm diameter)
B. 50 mL ethanol at 25°C in a 250 mL beaker (8 cm diameter)
C. 50 mL ethanol at 45°C in a 100 mL beaker (4 cm diameter)
D. 50 mL ethanol at 45°C in a 250 mL beaker (8 cm diameter)
E. 50 mL ethanol at 45°C in a 450 mL beaker (4 cm diameter)
Answer: D. 50 mL ethanol at 45°C in a 250 mL beaker (8 cm diameter)
, Explanation: Vaporization rate increases with temperature (higher average kinetic energy
enables more molecules to overcome intermolecular forces) and with increased surface area
(more molecules at the liquid-air interface can escape). Option D combines the highest
temperature (45°C) with the largest surface area (8 cm diameter beaker, which provides a wider
surface area than the 4 cm diameter beakers). Option E has the same temperature but a smaller
surface area.
Question 5
Germanium (bandgap 0.67 eV) is doped with boron. What is the resulting material?
A. n-type semiconductor
B. p-type semiconductor
C. Insulator
D. Superconductor
E. No change; bandgap is too small
Answer: B. p-type semiconductor
Explanation: Boron is a Group IIIA element with only three valence electrons, one fewer than
germanium's four. When boron substitutes for germanium in the crystal lattice, it creates electron
deficiencies (holes). These holes act as positive charge carriers, making the material a p-type
semiconductor. This process is called doping and is fundamental to semiconductor device
fabrication.
Question 6
Which statements about dipole-dipole forces are incorrect?
(1) Boiling a liquid requires sufficient energy to overcome all intermolecular attractions
(2) Weaker intermolecular attractions require more energy to separate particles
(3) Higher normal boiling points indicate stronger intermolecular attractive forces
(4) Boiling provides sufficient energy to break covalent bonds within molecules
2026/2027 | 150 Practice Questions with
Answers & Explanations | Study Guide for
Midterms & Finals
Description:
Master General Chemistry with this comprehensive 2026/2027 exam bank featuring 150
multiple-choice questions covering intermolecular forces, solutions, kinetics, acids and bases,
buffers, thermodynamics, electrochemistry, and nuclear chemistry. Each question includes a
detailed answer and expert explanation to reinforce your understanding of key concepts. Perfect
for university students preparing for midterms, finals, and standardized tests. This study
resource covers all major topics with practice problems, calculation examples, and concept
reviews aligned with current curriculum standards.
Download now and boost your exam performance with this essential chemistry study guide for
academic success in 2026/2027.
, CHEM 101 Exam Bank 2026/2027 – 150 Questions & Answers
PART A: STATES OF MATTER AND INTERMOLECULAR FORCES
Question 1
If a solid sample (not water) at its triple point undergoes a pressure increase of 150 torr while
temperature remains constant, in which phase will the sample exist?
A. Solid
B. Liquid
C. Gas
D. Plasma
E. Both gas and liquid properties
Answer: A. Solid
Explanation: At the triple point, all three phases coexist in equilibrium. The solid-liquid phase
boundary typically has a positive slope (for most substances except water), meaning that
increasing pressure at constant temperature favors the denser phase, which is generally the solid
phase. Therefore, the sample will transition to the solid phase.
Question 2
Which statement accurately describes the process of boiling?
A. High-energy molecules escape from the liquid, causing the average kinetic energy of the
remaining liquid to decrease
B. Molecules begin to adopt long-range order
C. Temperature continues to rise steadily as additional heat is supplied
D. The average kinetic energy of molecules in the liquid increases
E. The process is exothermic
Answer: A. High-energy molecules escape from the liquid, causing the average kinetic
energy of the remaining liquid to decrease
,Explanation: During boiling, the most energetic molecules overcome intermolecular forces and
escape into the gas phase. This selective removal of higher-energy molecules reduces the average
kinetic energy of the remaining liquid. The temperature remains constant during boiling as added
energy goes toward the phase change (enthalpy of vaporization) rather than increasing kinetic
energy.
Question 3
Based on intermolecular forces, determine the correct order of decreasing boiling points:
A. CH₄ > SnH₄ > H₂Te > H₂S > H₂O
B. H₂O > SnH₄ > H₂S > H₂Te > CH₄
C. H₂O > H₂Te > SnH₄ > H₂S > CH₄
D. H₂Te > H₂O > SnH₄ > H₂S > CH₄
E. SnH₄ > H₂S > H₂O > H₂Te > CH₄
Answer: C. H₂O > H₂Te > SnH₄ > H₂S > CH₄
Explanation: Water exhibits exceptionally strong hydrogen bonding, giving it the highest
boiling point despite its low molecular mass. For the chalcogen hydrides (H₂Te, H₂S), boiling
points generally increase with molecular mass due to stronger dispersion forces—thus H₂Te >
H₂S. SnH₄ has stronger dispersion forces than H₂S due to its larger molecular size, while CH₄ has
the lowest boiling point due to weak dispersion forces and no hydrogen bonding.
Question 4
Which sample of ethanol exhibits the greatest rate of vaporization?
A. 50 mL ethanol at 25°C in a 100 mL beaker (4 cm diameter)
B. 50 mL ethanol at 25°C in a 250 mL beaker (8 cm diameter)
C. 50 mL ethanol at 45°C in a 100 mL beaker (4 cm diameter)
D. 50 mL ethanol at 45°C in a 250 mL beaker (8 cm diameter)
E. 50 mL ethanol at 45°C in a 450 mL beaker (4 cm diameter)
Answer: D. 50 mL ethanol at 45°C in a 250 mL beaker (8 cm diameter)
, Explanation: Vaporization rate increases with temperature (higher average kinetic energy
enables more molecules to overcome intermolecular forces) and with increased surface area
(more molecules at the liquid-air interface can escape). Option D combines the highest
temperature (45°C) with the largest surface area (8 cm diameter beaker, which provides a wider
surface area than the 4 cm diameter beakers). Option E has the same temperature but a smaller
surface area.
Question 5
Germanium (bandgap 0.67 eV) is doped with boron. What is the resulting material?
A. n-type semiconductor
B. p-type semiconductor
C. Insulator
D. Superconductor
E. No change; bandgap is too small
Answer: B. p-type semiconductor
Explanation: Boron is a Group IIIA element with only three valence electrons, one fewer than
germanium's four. When boron substitutes for germanium in the crystal lattice, it creates electron
deficiencies (holes). These holes act as positive charge carriers, making the material a p-type
semiconductor. This process is called doping and is fundamental to semiconductor device
fabrication.
Question 6
Which statements about dipole-dipole forces are incorrect?
(1) Boiling a liquid requires sufficient energy to overcome all intermolecular attractions
(2) Weaker intermolecular attractions require more energy to separate particles
(3) Higher normal boiling points indicate stronger intermolecular attractive forces
(4) Boiling provides sufficient energy to break covalent bonds within molecules
