Chem 280 – General Chemistry (Allied Health) Midterm Exam
COMPLETE 200-PRACTICE-QUESTION BANK WITH VERIFIED
ANSWERS & EXPLANATIONS
BLOCK 1: MATTER, ENERGY, & MEASUREMENT (Questions 1–25)
Q1. Chemistry is the study of:
A) Living organisms only
B) Matter and its transformations
C) Mathematical principles
D) The Earth’s geological composition
Answer: B
Explanation: Chemistry is the science that studies the composition, structure, properties, and changes of
matter (the material that makes up the universe).
Q2. Which of the following would NOT be an example of “quantification”?
A) The newest model car gets 5 more miles per gallon than last year’s model.
B) The average high temperature this July was 2 degrees higher than last year’s.
C) The price of milk went up 10 cents per gallon.
D) The water in the swimming pool feels colder than it was yesterday.
Answer: D
Explanation: “Feels colder” is a qualitative, subjective observation. Quantification involves making a
measurement with a number and a unit.
Q3. The SI base unit of length is the:
A) Centimeter
,B) Meter
C) Kilometer
D) Inch
Answer: B
Explanation: The meter (m) is the SI base unit for length. All other length units are derived from it.
Q4. The SI base unit of mass is the:
A) Gram
B) Pound
C) Kilogram
D) Ounce
Answer: C
Explanation: The kilogram (kg) is the SI base unit of mass. The gram, while commonly used, is a derived
unit.
Q5. The SI base unit of time is the:
A) Minute
B) Hour
C) Second
D) Day
Answer: C
Explanation: The second (s) is the SI base unit of time.
Q6. Which prefix has a multiplier of \(10^{-3}\)?
A) Milli
B) Centi
,C) Micro
D) Kilo
Answer: A
Explanation: The prefix milli‑ stands for \( \frac{1}{1000} = 10^{-3} \).
Q7. Which prefix represents \(10^{-2}\)?
A) Milli
B) Centi
C) Micro
D) Nano
Answer: B
Explanation: The prefix centi‑ means “one‑hundredth,” i.e., \(10^{-2}\).
Q8. The correct number of significant figures in 0.002320 is:
A) 7
B) 4
C) 3
D) Ambiguous
Answer: B
Explanation: Leading zeros are not significant; the zeros after the 2 are significant because they follow a
non‑zero digit. The digits “2320” give 4 significant figures.
Q9. How many significant figures are in the measurement \( 1.050 \times 10^{3} \) g?
A) 2
B) 3
C) 4
, D) 5
Answer: C
Explanation: All digits in the coefficient (1, 0, 5, 0) are significant because the zeros are between and at
the end after the decimal.
Q10. Convert \( 0.00032400 \) to scientific notation with the correct number of significant figures.
A) \( 3.24 \times 10^{-4} \)
B) \( 3.2400 \times 10^{-4} \)
C) \( 3.2 \times 10^{-4} \)
D) \( 3.240 \times 10^{-4} \)
Answer: B
Explanation: The trailing zeros after the 4 are significant, so they must be shown in the coefficient. \(
3.2400 \times 10^{-4} \) has the correct 5 significant figures.
Q11. A solution is an example of:
A) Heterogeneous mixture
B) Homogeneous mixture
C) Element
D) Compound
Answer: B
Explanation: In a solution the solute particles are uniformly dispersed, so it is a homogeneous mixture.
Q12. Which separation technique is best for recovering a solid solute from a solution?
A) Filtration
B) Distillation
C) Evaporation
COMPLETE 200-PRACTICE-QUESTION BANK WITH VERIFIED
ANSWERS & EXPLANATIONS
BLOCK 1: MATTER, ENERGY, & MEASUREMENT (Questions 1–25)
Q1. Chemistry is the study of:
A) Living organisms only
B) Matter and its transformations
C) Mathematical principles
D) The Earth’s geological composition
Answer: B
Explanation: Chemistry is the science that studies the composition, structure, properties, and changes of
matter (the material that makes up the universe).
Q2. Which of the following would NOT be an example of “quantification”?
A) The newest model car gets 5 more miles per gallon than last year’s model.
B) The average high temperature this July was 2 degrees higher than last year’s.
C) The price of milk went up 10 cents per gallon.
D) The water in the swimming pool feels colder than it was yesterday.
Answer: D
Explanation: “Feels colder” is a qualitative, subjective observation. Quantification involves making a
measurement with a number and a unit.
Q3. The SI base unit of length is the:
A) Centimeter
,B) Meter
C) Kilometer
D) Inch
Answer: B
Explanation: The meter (m) is the SI base unit for length. All other length units are derived from it.
Q4. The SI base unit of mass is the:
A) Gram
B) Pound
C) Kilogram
D) Ounce
Answer: C
Explanation: The kilogram (kg) is the SI base unit of mass. The gram, while commonly used, is a derived
unit.
Q5. The SI base unit of time is the:
A) Minute
B) Hour
C) Second
D) Day
Answer: C
Explanation: The second (s) is the SI base unit of time.
Q6. Which prefix has a multiplier of \(10^{-3}\)?
A) Milli
B) Centi
,C) Micro
D) Kilo
Answer: A
Explanation: The prefix milli‑ stands for \( \frac{1}{1000} = 10^{-3} \).
Q7. Which prefix represents \(10^{-2}\)?
A) Milli
B) Centi
C) Micro
D) Nano
Answer: B
Explanation: The prefix centi‑ means “one‑hundredth,” i.e., \(10^{-2}\).
Q8. The correct number of significant figures in 0.002320 is:
A) 7
B) 4
C) 3
D) Ambiguous
Answer: B
Explanation: Leading zeros are not significant; the zeros after the 2 are significant because they follow a
non‑zero digit. The digits “2320” give 4 significant figures.
Q9. How many significant figures are in the measurement \( 1.050 \times 10^{3} \) g?
A) 2
B) 3
C) 4
, D) 5
Answer: C
Explanation: All digits in the coefficient (1, 0, 5, 0) are significant because the zeros are between and at
the end after the decimal.
Q10. Convert \( 0.00032400 \) to scientific notation with the correct number of significant figures.
A) \( 3.24 \times 10^{-4} \)
B) \( 3.2400 \times 10^{-4} \)
C) \( 3.2 \times 10^{-4} \)
D) \( 3.240 \times 10^{-4} \)
Answer: B
Explanation: The trailing zeros after the 4 are significant, so they must be shown in the coefficient. \(
3.2400 \times 10^{-4} \) has the correct 5 significant figures.
Q11. A solution is an example of:
A) Heterogeneous mixture
B) Homogeneous mixture
C) Element
D) Compound
Answer: B
Explanation: In a solution the solute particles are uniformly dispersed, so it is a homogeneous mixture.
Q12. Which separation technique is best for recovering a solid solute from a solution?
A) Filtration
B) Distillation
C) Evaporation
