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CHEM 103 (PREPARATORY CHEMISTRY) EXAM 1 AT UNLV, NEWEST
UPDATED EXAM 2026 – 2027 SOLVED QUESTIONS & ANSWERS VERIFIED
100% GRADED A+ (LATEST VERSION)
1. Which SI base unit should a CHEM 103 student use when reporting the measured
length of a laboratory bench during an experiment?
A. Meter
B. Liter
C. Gram
D. Kelvin
Answer: A
Rationale: The SI base unit for length is the meter (m); liter measures volume, gram is
commonly used for mass although kilogram is the SI base unit, and kelvin measures
temperature.
2. Which metric prefix represents a factor of one thousand when converting
between related SI measurements in introductory chemistry calculations?
A. Centi-
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B. Milli-
C. Kilo-
D. Micro-
Answer: C
Rationale: Kilo- means 1,000 (10³), so 1 kilometer equals 1,000 meters; centi- is 10⁻²,
milli- is 10⁻³, and micro- is 10⁻⁶.
3. How many milliliters are contained in exactly 2.50 liters when the metric
relationship between liters and milliliters is applied correctly?
A. 0.00250 mL
B. 25.0 mL
C. 250 mL
D. 2,500 mL
Answer: D
Rationale: Since 1 L = 1,000 mL, multiplying 2.50 L by 1,000 mL/L gives 2,500 mL after
the liters cancel.
4. Which of the following is the SI base unit for mass, as distinguished from the
commonly used gram in laboratory measurements?
A. Pound
B. Kilogram
C. Ounce
D. Ton
Answer: B
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Rationale: The SI base unit for mass is the kilogram (kg), although the gram is
commonly used in laboratory work; the pound, ounce, and ton are not SI units.
5. Which metric prefix would a student apply to convert 0.005 meters into
millimeters for a laboratory measurement?
A. The student should multiply by 1,000 because milli- means 10⁻³.
B. The student should divide by 1,000 because milli- means 10³.
C. The student should multiply by 100 because milli- means 10⁻².
D. The student should divide by 100 because milli- means 10².
Answer: A
Rationale: Milli- means 10⁻³, so 0.005 m × 1,000 mm/m = 5 mm.
6. Which of the following measurements is expressed with the correct SI unit for
temperature in scientific laboratory work?
A. 25 Celsius
B. 25 Kelvin
C. 25 Fahrenheit
D. 25 Celsius degrees
Answer: B
Rationale: The SI base unit for thermodynamic temperature is the kelvin (K), written
without the degree symbol; Celsius and Fahrenheit are non-SI temperature scales.
7. Which of the following represents the correct conversion of 3.75 kilograms into
grams using the metric relationship between the units?
A. 0.00375 g
B. 37.5 g
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C. 375 g
D. 3,750 g
Answer: D
Rationale: Since 1 kg = 1,000 g, multiplying 3.75 kg by 1,000 g/kg gives 3,750 g.
8. Which of the following best explains why a numerical value without an
appropriate unit does not completely describe a physical measurement?
A. Because numbers are always exact in chemistry
B. Because the unit identifies the dimension and scale of the measurement
C. Because units are optional in laboratory reports
D. Because only derived units are meaningful
Answer: B
Rationale: A numerical value without an appropriate unit does not completely describe
a physical measurement because the unit identifies what dimension is being measured
and on what scale.
9. Which of the following is an example of a derived SI unit rather than a base SI
unit?
A. Meter
B. Kilogram
C. Second
D. Liter
Answer: D
Rationale: The liter is a derived unit of volume, whereas the meter, kilogram, and
second are base SI units.
CHEM 103 (PREPARATORY CHEMISTRY) EXAM 1 AT UNLV, NEWEST
UPDATED EXAM 2026 – 2027 SOLVED QUESTIONS & ANSWERS VERIFIED
100% GRADED A+ (LATEST VERSION)
1. Which SI base unit should a CHEM 103 student use when reporting the measured
length of a laboratory bench during an experiment?
A. Meter
B. Liter
C. Gram
D. Kelvin
Answer: A
Rationale: The SI base unit for length is the meter (m); liter measures volume, gram is
commonly used for mass although kilogram is the SI base unit, and kelvin measures
temperature.
2. Which metric prefix represents a factor of one thousand when converting
between related SI measurements in introductory chemistry calculations?
A. Centi-
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B. Milli-
C. Kilo-
D. Micro-
Answer: C
Rationale: Kilo- means 1,000 (10³), so 1 kilometer equals 1,000 meters; centi- is 10⁻²,
milli- is 10⁻³, and micro- is 10⁻⁶.
3. How many milliliters are contained in exactly 2.50 liters when the metric
relationship between liters and milliliters is applied correctly?
A. 0.00250 mL
B. 25.0 mL
C. 250 mL
D. 2,500 mL
Answer: D
Rationale: Since 1 L = 1,000 mL, multiplying 2.50 L by 1,000 mL/L gives 2,500 mL after
the liters cancel.
4. Which of the following is the SI base unit for mass, as distinguished from the
commonly used gram in laboratory measurements?
A. Pound
B. Kilogram
C. Ounce
D. Ton
Answer: B
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Rationale: The SI base unit for mass is the kilogram (kg), although the gram is
commonly used in laboratory work; the pound, ounce, and ton are not SI units.
5. Which metric prefix would a student apply to convert 0.005 meters into
millimeters for a laboratory measurement?
A. The student should multiply by 1,000 because milli- means 10⁻³.
B. The student should divide by 1,000 because milli- means 10³.
C. The student should multiply by 100 because milli- means 10⁻².
D. The student should divide by 100 because milli- means 10².
Answer: A
Rationale: Milli- means 10⁻³, so 0.005 m × 1,000 mm/m = 5 mm.
6. Which of the following measurements is expressed with the correct SI unit for
temperature in scientific laboratory work?
A. 25 Celsius
B. 25 Kelvin
C. 25 Fahrenheit
D. 25 Celsius degrees
Answer: B
Rationale: The SI base unit for thermodynamic temperature is the kelvin (K), written
without the degree symbol; Celsius and Fahrenheit are non-SI temperature scales.
7. Which of the following represents the correct conversion of 3.75 kilograms into
grams using the metric relationship between the units?
A. 0.00375 g
B. 37.5 g
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C. 375 g
D. 3,750 g
Answer: D
Rationale: Since 1 kg = 1,000 g, multiplying 3.75 kg by 1,000 g/kg gives 3,750 g.
8. Which of the following best explains why a numerical value without an
appropriate unit does not completely describe a physical measurement?
A. Because numbers are always exact in chemistry
B. Because the unit identifies the dimension and scale of the measurement
C. Because units are optional in laboratory reports
D. Because only derived units are meaningful
Answer: B
Rationale: A numerical value without an appropriate unit does not completely describe
a physical measurement because the unit identifies what dimension is being measured
and on what scale.
9. Which of the following is an example of a derived SI unit rather than a base SI
unit?
A. Meter
B. Kilogram
C. Second
D. Liter
Answer: D
Rationale: The liter is a derived unit of volume, whereas the meter, kilogram, and
second are base SI units.
