Advanced Test Bank (28 Questions + Rationales)
1. Which of the following best illustrates the scientific method in
chemistry?
A. Accepting a hypothesis as true based on intuition
B. Designing an experiment to test a falsifiable hypothesis
C. Using deductive reasoning from axioms alone
D. Applying a known theory without questioning
✅ Correct Answer: B
📘 Rationale: The scientific method emphasizes empirical evidence,
testable hypotheses, and falsifiability. Designing experiments is a core
principle, unlike intuition or blind application of theory.
2. Which step in the scientific method must directly precede the
formulation of a theory?
A. Asking a question
B. Conducting a controlled experiment
C. Observing consistent experimental results
D. Making a prediction
✅ Correct Answer: C
📘 Rationale: A theory arises from a body of consistent experimental
data. While questions and predictions are part of the method,
reproducibility of results is crucial before theory development.
,3. A sample of an unknown gas occupies 22.4 L at STP. What type of
observation is this?
A. Quantitative
B. Qualitative
C. Inferential
D. Hypothetical
✅ Correct Answer: A
📘 Rationale: Numerical measurements like volume are quantitative
observations. Qualitative refers to characteristics like color or odor.
4. Which of the following is a derived SI unit?
A. Meter
B. Kelvin
C. Joule
D. Mole
✅ Correct Answer: C
📘 Rationale: The joule (J) is derived from base units (kg·m²/s²).
Others listed are fundamental SI units.
5. The metric prefix "nano-" means:
A. 10−310^{-3}10−3
B. 10−610^{-6}10−6
C. 10−910^{-9}10−9
D. 10−1210^{-12}10−12
, ✅ Correct Answer: C
📘 Rationale: "Nano-" denotes 10−910^{-9}10−9, as used in
nanometers (nm), nanoseconds (ns), etc.
6. The best term for a substance that has variable composition is:
A. Pure substance
B. Homogeneous mixture
C. Compound
D. Element
✅ Correct Answer: B
📘 Rationale: Homogeneous mixtures, like air or alloys, are uniform
but have variable composition. Compounds and elements are fixed in
composition.
7. Which process is not a chemical change?
A. Rusting of iron
B. Dissolving sugar in water
C. Combustion of propane
D. Decomposition of water
✅ Correct Answer: B
📘 Rationale: Sugar dissolving is a physical change. No new
substances form.
8. Which has the highest number of significant figures?