CHEM 1020 Exam | Actual Questions and
Answers Latest Updated 2026/2027
(Graded A+)
Section 1: Matter, Measurement & Significant Figures
1. Which of the following is a homogeneous mixture?
A. Granite
B. Salt water
C. Sand and iron filings
D. Oil and water
Correct Answer: B
Rationale: Salt water has uniform composition throughout — the salt is
fully dissolved. Granite, sand/iron, and oil/water are heterogeneous (visible
distinct regions).
2. Which is a chemical change?
A. Melting ice
B. Boiling water
C. Burning wood
D. Dissolving sugar
Correct Answer: C
Rationale: Burning wood produces new substances (CO₂, H₂O, ash) —
composition changes. Melting, boiling, and dissolving are physical changes.
3. The law of conservation of mass states that:
A. Mass is created in reactions
B. Mass is destroyed in reactions
C. Mass is neither created nor destroyed in chemical reactions
D. Mass equals energy
, Correct Answer: C
Rationale: Lavoisier's law: total reactant mass = total product mass in a
chemical reaction.
4. How many significant figures are in 0.004050?
A. 3
B. 4
C. 5
D. 6
Correct Answer: B
Rationale: Leading zeros don't count; the digits 4, 0, 5, and the trailing
zero count = 4 sig figs.
5. Which is an intensive property?
A. Mass
B. Volume
C. Density
D. Length
Correct Answer: C
Rationale: Intensive properties don't depend on sample size. Density is
intensive; mass, volume, and length are extensive.
6. Convert 37°C to Kelvin.
A. 236 K
B. 310 K
C. 273 K
D. 100 K
Correct Answer: B
Rationale: K = °C + 273.15 = 37 + 273 = 310 K.
,7. SATA: Which are physical properties? (Select all that apply.)
A. Density
B. Flammability
C. Melting point
D. Reactivity with acid
E. Color
Correct Answers: A, C, E
Rationale: Density, melting point, and color are observable without
changing identity. Flammability and acid reactivity are chemical properties.
8. The prefix "kilo-" represents:
A. 10⁻³
B. 10³
C. 10⁶
D. 10⁻⁶
Correct Answer: B
Rationale: Kilo- = 10³ (e.g., 1 km = 1000 m). Milli- = 10⁻³, mega- = 10⁶,
micro- = 10⁻⁶.
9. How many mL are in 2.5 L?
A. 25 mL
B. 250 mL
C. 2500 mL
D. 25,000 mL
Correct Answer: C
Rationale: 1 L = 1000 mL, so 2.5 × 1000 = 2500 mL.
10. A substance that cannot be broken down into simpler substances by
chemical means is a(n):
A. Compound
, B. Mixture
C. Element
D. Solution
Correct Answer: C
Rationale: Elements are the simplest pure substances. Compounds can be
broken into elements; mixtures can be separated physically.
11. Which state of matter is compressible?
A. Solid
B. Liquid
C. Gas
D. All equally
Correct Answer: C
Rationale: Gases have large spaces between particles, making them
compressible. Solids and liquids are nearly incompressible.
12. SATA: Which are SI base units? (Select all that apply.)
A. Meter
B. Kilogram
C. Liter
D. Second
E. Kelvin
Correct Answers: A, B, D, E
Rationale: SI base units include meter, kilogram, second, kelvin, mole,
ampere, and candela. The liter is a derived/non-SI unit.
13. Density of a 25.0 g sample occupying 5.0 mL is:
A. 0.20 g/mL
B. 5.0 g/mL
Answers Latest Updated 2026/2027
(Graded A+)
Section 1: Matter, Measurement & Significant Figures
1. Which of the following is a homogeneous mixture?
A. Granite
B. Salt water
C. Sand and iron filings
D. Oil and water
Correct Answer: B
Rationale: Salt water has uniform composition throughout — the salt is
fully dissolved. Granite, sand/iron, and oil/water are heterogeneous (visible
distinct regions).
2. Which is a chemical change?
A. Melting ice
B. Boiling water
C. Burning wood
D. Dissolving sugar
Correct Answer: C
Rationale: Burning wood produces new substances (CO₂, H₂O, ash) —
composition changes. Melting, boiling, and dissolving are physical changes.
3. The law of conservation of mass states that:
A. Mass is created in reactions
B. Mass is destroyed in reactions
C. Mass is neither created nor destroyed in chemical reactions
D. Mass equals energy
, Correct Answer: C
Rationale: Lavoisier's law: total reactant mass = total product mass in a
chemical reaction.
4. How many significant figures are in 0.004050?
A. 3
B. 4
C. 5
D. 6
Correct Answer: B
Rationale: Leading zeros don't count; the digits 4, 0, 5, and the trailing
zero count = 4 sig figs.
5. Which is an intensive property?
A. Mass
B. Volume
C. Density
D. Length
Correct Answer: C
Rationale: Intensive properties don't depend on sample size. Density is
intensive; mass, volume, and length are extensive.
6. Convert 37°C to Kelvin.
A. 236 K
B. 310 K
C. 273 K
D. 100 K
Correct Answer: B
Rationale: K = °C + 273.15 = 37 + 273 = 310 K.
,7. SATA: Which are physical properties? (Select all that apply.)
A. Density
B. Flammability
C. Melting point
D. Reactivity with acid
E. Color
Correct Answers: A, C, E
Rationale: Density, melting point, and color are observable without
changing identity. Flammability and acid reactivity are chemical properties.
8. The prefix "kilo-" represents:
A. 10⁻³
B. 10³
C. 10⁶
D. 10⁻⁶
Correct Answer: B
Rationale: Kilo- = 10³ (e.g., 1 km = 1000 m). Milli- = 10⁻³, mega- = 10⁶,
micro- = 10⁻⁶.
9. How many mL are in 2.5 L?
A. 25 mL
B. 250 mL
C. 2500 mL
D. 25,000 mL
Correct Answer: C
Rationale: 1 L = 1000 mL, so 2.5 × 1000 = 2500 mL.
10. A substance that cannot be broken down into simpler substances by
chemical means is a(n):
A. Compound
, B. Mixture
C. Element
D. Solution
Correct Answer: C
Rationale: Elements are the simplest pure substances. Compounds can be
broken into elements; mixtures can be separated physically.
11. Which state of matter is compressible?
A. Solid
B. Liquid
C. Gas
D. All equally
Correct Answer: C
Rationale: Gases have large spaces between particles, making them
compressible. Solids and liquids are nearly incompressible.
12. SATA: Which are SI base units? (Select all that apply.)
A. Meter
B. Kilogram
C. Liter
D. Second
E. Kelvin
Correct Answers: A, B, D, E
Rationale: SI base units include meter, kilogram, second, kelvin, mole,
ampere, and candela. The liter is a derived/non-SI unit.
13. Density of a 25.0 g sample occupying 5.0 mL is:
A. 0.20 g/mL
B. 5.0 g/mL
