CHEM 103 (General Chemistry) Module 4
2026 CHEM 103 (General Chemistry)
Module 4 Practice Exam 100 Questions
and Answers with Rationales
Questions 1–25
Fundamentals of Solutions, Solubility, Molarity &
Precipitation
1. Which term describes a homogeneous mixture of two or more substances?
A. Suspension
B. Colloid
C. ✅✅ Solution
D. Alloy
Answer: ✅✅ C
Rationale:
A solution is a homogeneous mixture in which the solute is uniformly dispersed throughout the
solvent.
2. Which component of a solution is usually present in the greatest amount?
A. Solute
B. ✅✅ Solvent
C. Precipitate
D. Electrolyte
Answer: ✅✅ B
, CHEM 103 (General Chemistry) Module 4
Rationale:
The solvent is the substance that dissolves the solute and is present in the largest quantity.
3. What is the SI unit commonly used to express solution concentration in
general chemistry?
A. ppm
B. ✅✅ Molarity (mol/L)
C. Density
D. Molality
Answer: ✅✅ B
Rationale:
Molarity is defined as moles of solute per liter of solution and is the most common concentration
unit in introductory chemistry.
4. Molarity is defined as:
M=nVM = \frac{n}{V}M=Vn
M=1.2 mol0.8 L=1.5 mol/LM=\frac{1.2\,\mathrm{mol}}{0.8\,\mathrm{L}}=1.5\,\mathrm{mol/
L}M=0.8L1.2mol=1.5mol/L
nnn
mol
VVV
L
A. grams of solute per liter
B. moles of solvent per liter
C. ✅✅ moles of solute per liter of solution
D. grams of solvent per kilogram
Answer: ✅✅ C
, CHEM 103 (General Chemistry) Module 4
Rationale:
Molarity (M) equals the number of moles of solute divided by the total volume of solution in
liters.
5. Which substance is a strong electrolyte?
A. Sugar (C₁₂H₂₂O₁₁)
B. Ethanol (C₂H₅OH)
C. ✅✅ Sodium chloride (NaCl)
D. Urea
Answer: ✅✅ C
Rationale:
NaCl dissociates completely into Na⁺ and Cl⁻ ions in water, making it a strong electrolyte.
6. Which compound is generally insoluble in water?
A. NaNO₃
B. KCl
C. ✅✅ AgCl
D. NH₄NO₃
Answer: ✅✅ C
Rationale:
Most silver salts are insoluble except silver nitrate and a few others.
7. Which ion forms a precipitate with Ag⁺?
A. NO₃⁻
B. NH₄⁺
, CHEM 103 (General Chemistry) Module 4
C. ✅✅ Cl⁻
D. Na⁺
Answer: ✅✅ C
Rationale:
Silver chloride (AgCl) is an insoluble white precipitate.
8. Which equation represents a precipitation reaction?
A. HCl + NaOH → NaCl + H₂O
B. CH₄ + 2O₂ → CO₂ + 2H₂O
C. ✅✅ AgNO₃ + NaCl → AgCl(s) + NaNO₃
D. Zn + CuSO₄ → ZnSO₄ + Cu
Answer: ✅✅ C
Rationale:
A precipitate forms when two aqueous ionic compounds produce an insoluble product.
9. Which ion is always soluble in water?
A. Ag⁺
B. Pb²⁺
C. ✅✅ NO₃⁻
D. CO₃²⁻
Answer: ✅✅ C
Rationale:
All nitrate salts are soluble.
2026 CHEM 103 (General Chemistry)
Module 4 Practice Exam 100 Questions
and Answers with Rationales
Questions 1–25
Fundamentals of Solutions, Solubility, Molarity &
Precipitation
1. Which term describes a homogeneous mixture of two or more substances?
A. Suspension
B. Colloid
C. ✅✅ Solution
D. Alloy
Answer: ✅✅ C
Rationale:
A solution is a homogeneous mixture in which the solute is uniformly dispersed throughout the
solvent.
2. Which component of a solution is usually present in the greatest amount?
A. Solute
B. ✅✅ Solvent
C. Precipitate
D. Electrolyte
Answer: ✅✅ B
, CHEM 103 (General Chemistry) Module 4
Rationale:
The solvent is the substance that dissolves the solute and is present in the largest quantity.
3. What is the SI unit commonly used to express solution concentration in
general chemistry?
A. ppm
B. ✅✅ Molarity (mol/L)
C. Density
D. Molality
Answer: ✅✅ B
Rationale:
Molarity is defined as moles of solute per liter of solution and is the most common concentration
unit in introductory chemistry.
4. Molarity is defined as:
M=nVM = \frac{n}{V}M=Vn
M=1.2 mol0.8 L=1.5 mol/LM=\frac{1.2\,\mathrm{mol}}{0.8\,\mathrm{L}}=1.5\,\mathrm{mol/
L}M=0.8L1.2mol=1.5mol/L
nnn
mol
VVV
L
A. grams of solute per liter
B. moles of solvent per liter
C. ✅✅ moles of solute per liter of solution
D. grams of solvent per kilogram
Answer: ✅✅ C
, CHEM 103 (General Chemistry) Module 4
Rationale:
Molarity (M) equals the number of moles of solute divided by the total volume of solution in
liters.
5. Which substance is a strong electrolyte?
A. Sugar (C₁₂H₂₂O₁₁)
B. Ethanol (C₂H₅OH)
C. ✅✅ Sodium chloride (NaCl)
D. Urea
Answer: ✅✅ C
Rationale:
NaCl dissociates completely into Na⁺ and Cl⁻ ions in water, making it a strong electrolyte.
6. Which compound is generally insoluble in water?
A. NaNO₃
B. KCl
C. ✅✅ AgCl
D. NH₄NO₃
Answer: ✅✅ C
Rationale:
Most silver salts are insoluble except silver nitrate and a few others.
7. Which ion forms a precipitate with Ag⁺?
A. NO₃⁻
B. NH₄⁺
, CHEM 103 (General Chemistry) Module 4
C. ✅✅ Cl⁻
D. Na⁺
Answer: ✅✅ C
Rationale:
Silver chloride (AgCl) is an insoluble white precipitate.
8. Which equation represents a precipitation reaction?
A. HCl + NaOH → NaCl + H₂O
B. CH₄ + 2O₂ → CO₂ + 2H₂O
C. ✅✅ AgNO₃ + NaCl → AgCl(s) + NaNO₃
D. Zn + CuSO₄ → ZnSO₄ + Cu
Answer: ✅✅ C
Rationale:
A precipitate forms when two aqueous ionic compounds produce an insoluble product.
9. Which ion is always soluble in water?
A. Ag⁺
B. Pb²⁺
C. ✅✅ NO₃⁻
D. CO₃²⁻
Answer: ✅✅ C
Rationale:
All nitrate salts are soluble.
