UNE GENERAL CHEMISTRY II MIDTERM EXAM WEEKS 1-7
ACTUAL 2026/2027 PRACTICE QUESTIONS AND STUDY GUIDE
COMPLETE ACCURATE EXAM APPROVED QUESTIONS AND
CORRECT DETAILED ANSWERS WITH RATIONALES (100%
CORRECT VERIFIED SOLUTIONS) CURRENTLY UPDATED
VERSION 2026 EDITION |GUARANTEED SUCCESS A+ (BRAND
NEW!) FULL REVISED UNE GENERAL CHEMISTRY II REAL
MIDTERM EXAM WEEKS 1-7|JUST RELEASED
At room temperature and 1 atm, methane (CH₄) is a gas and carbon
tetrachloride (CCl₄) is a liquid. Which intermolecular force is
primarily responsible for this phase difference?
A) Hydrogen bonding
B) London dispersion forces
C) Dipole-dipole interactions
D) Ion-dipole forces
Correct Answer: B
Rationale: Both CH₄ and CCl₄ are nonpolar molecules; the only
intermolecular forces present are London dispersion forces (also
called dispersion forces or induced dipole-induced dipole
interactions). CCl₄ has a much larger electron cloud and greater
polarizability than CH₄, leading to significantly stronger dispersion
forces, which result in a liquid phase at room temperature, whereas
CH₄ remains a gas.
Which of the following will have the lowest boiling point?
A) CH₃CH₂OH
B) CH₃OCH₃
,C) CH₃CH₃
D) CH₃Cl
Correct Answer: C
Rationale: CH₃CH₃ (ethane) is a nonpolar molecule that exhibits
only weak London dispersion forces. The other compounds have
stronger intermolecular forces: CH₃CH₂OH has hydrogen bonding,
CH₃OCH₃ has dipole-dipole interactions, and CH₃Cl has dipole-
dipole interactions. Weaker intermolecular forces correlate with
lower boiling points.
Which of the following processes is endothermic?
A) Vaporization
B) Condensation
C) Freezing
D) Deposition
Correct Answer: A
Rationale: Vaporization (liquid → gas) requires energy input to
overcome intermolecular forces, making it endothermic. The reverse
processes—condensation, freezing, and deposition—are exothermic
because they release energy as intermolecular forces form.
Which of the following is true about solutions?
A) A solution will not spontaneously separate
B) A solution will spontaneously separate into its components over
time
C) A solution is always a homogeneous mixture of two liquids
,D) A solution must contain water as the solvent
Correct Answer: A
Rationale: A solution is a homogeneous mixture that is stable; its
components do not spontaneously separate because the solute
particles are uniformly dispersed and the entropy of mixing favors
the mixed state.
In the dissolution of an ionic compound in water, which step is
always endothermic?
A) The overall process of dissolution
B) The separation of solute ions (lattice energy)
C) The hydration of ions
D) The mixing of solute and solvent
Correct Answer: B
Rationale: The separation of ions from the ionic lattice (breaking
ionic bonds) always requires energy input and is therefore always
endothermic. Hydration of ions is exothermic, and the overall
dissolution can be either endothermic or exothermic depending on
the relative magnitudes of lattice energy and hydration energy.
The solubility of sucrose in water at 20°C is 6.13 mol/L. If 6.55 mol
of sucrose is dissolved in 1.00 L of water at 90°C and allowed to cool
to 20°C with no formation of solid sucrose, the resulting solution is:
A) Supersaturated
B) Saturated
C) Unsaturated
, D) A colloid
Correct Answer: A
Rationale: At 20°C, the maximum solubility is 6.13 mol/L.
Dissolving 6.55 mol in 1.00 L exceeds this limit. If no solid forms
upon cooling, the solution contains more dissolved solute than the
equilibrium solubility allows, which defines a supersaturated
solution—a metastable state.
The solubility of sucrose in water at 20°C is 6.13 mol/L. If 5.72 mol
of sucrose is dissolved in 1.00 L of water at 90°C and allowed to cool
to 20°C with no formation of solid sucrose, the resulting solution is:
A) Supersaturated
B) Saturated
C) Unsaturated
D) A suspension
Correct Answer: C
Rationale: At 20°C, the solubility is 6.13 mol/L. Since 5.72 mol is
less than 6.13 mol, the solution can dissolve more solute; it is
unsaturated. No precipitation occurs because the amount dissolved is
below the saturation limit.
Which statement is always true, even if two solutions contain
different solutes?
A) The nonvolatile solute, temperature, and pressure are the same
for all solutions
ACTUAL 2026/2027 PRACTICE QUESTIONS AND STUDY GUIDE
COMPLETE ACCURATE EXAM APPROVED QUESTIONS AND
CORRECT DETAILED ANSWERS WITH RATIONALES (100%
CORRECT VERIFIED SOLUTIONS) CURRENTLY UPDATED
VERSION 2026 EDITION |GUARANTEED SUCCESS A+ (BRAND
NEW!) FULL REVISED UNE GENERAL CHEMISTRY II REAL
MIDTERM EXAM WEEKS 1-7|JUST RELEASED
At room temperature and 1 atm, methane (CH₄) is a gas and carbon
tetrachloride (CCl₄) is a liquid. Which intermolecular force is
primarily responsible for this phase difference?
A) Hydrogen bonding
B) London dispersion forces
C) Dipole-dipole interactions
D) Ion-dipole forces
Correct Answer: B
Rationale: Both CH₄ and CCl₄ are nonpolar molecules; the only
intermolecular forces present are London dispersion forces (also
called dispersion forces or induced dipole-induced dipole
interactions). CCl₄ has a much larger electron cloud and greater
polarizability than CH₄, leading to significantly stronger dispersion
forces, which result in a liquid phase at room temperature, whereas
CH₄ remains a gas.
Which of the following will have the lowest boiling point?
A) CH₃CH₂OH
B) CH₃OCH₃
,C) CH₃CH₃
D) CH₃Cl
Correct Answer: C
Rationale: CH₃CH₃ (ethane) is a nonpolar molecule that exhibits
only weak London dispersion forces. The other compounds have
stronger intermolecular forces: CH₃CH₂OH has hydrogen bonding,
CH₃OCH₃ has dipole-dipole interactions, and CH₃Cl has dipole-
dipole interactions. Weaker intermolecular forces correlate with
lower boiling points.
Which of the following processes is endothermic?
A) Vaporization
B) Condensation
C) Freezing
D) Deposition
Correct Answer: A
Rationale: Vaporization (liquid → gas) requires energy input to
overcome intermolecular forces, making it endothermic. The reverse
processes—condensation, freezing, and deposition—are exothermic
because they release energy as intermolecular forces form.
Which of the following is true about solutions?
A) A solution will not spontaneously separate
B) A solution will spontaneously separate into its components over
time
C) A solution is always a homogeneous mixture of two liquids
,D) A solution must contain water as the solvent
Correct Answer: A
Rationale: A solution is a homogeneous mixture that is stable; its
components do not spontaneously separate because the solute
particles are uniformly dispersed and the entropy of mixing favors
the mixed state.
In the dissolution of an ionic compound in water, which step is
always endothermic?
A) The overall process of dissolution
B) The separation of solute ions (lattice energy)
C) The hydration of ions
D) The mixing of solute and solvent
Correct Answer: B
Rationale: The separation of ions from the ionic lattice (breaking
ionic bonds) always requires energy input and is therefore always
endothermic. Hydration of ions is exothermic, and the overall
dissolution can be either endothermic or exothermic depending on
the relative magnitudes of lattice energy and hydration energy.
The solubility of sucrose in water at 20°C is 6.13 mol/L. If 6.55 mol
of sucrose is dissolved in 1.00 L of water at 90°C and allowed to cool
to 20°C with no formation of solid sucrose, the resulting solution is:
A) Supersaturated
B) Saturated
C) Unsaturated
, D) A colloid
Correct Answer: A
Rationale: At 20°C, the maximum solubility is 6.13 mol/L.
Dissolving 6.55 mol in 1.00 L exceeds this limit. If no solid forms
upon cooling, the solution contains more dissolved solute than the
equilibrium solubility allows, which defines a supersaturated
solution—a metastable state.
The solubility of sucrose in water at 20°C is 6.13 mol/L. If 5.72 mol
of sucrose is dissolved in 1.00 L of water at 90°C and allowed to cool
to 20°C with no formation of solid sucrose, the resulting solution is:
A) Supersaturated
B) Saturated
C) Unsaturated
D) A suspension
Correct Answer: C
Rationale: At 20°C, the solubility is 6.13 mol/L. Since 5.72 mol is
less than 6.13 mol, the solution can dissolve more solute; it is
unsaturated. No precipitation occurs because the amount dissolved is
below the saturation limit.
Which statement is always true, even if two solutions contain
different solutes?
A) The nonvolatile solute, temperature, and pressure are the same
for all solutions
