Chem 103 Module 1 to 6 Exam answers Portage learning | Graded A+ Latest 2026/2027 -
2026/2027 Official Exam
OBJECTIVE ASSESSMENT - EXAM
Chem 103 Module 1 to 6 Exam
answers Portage learning |
Graded A+ Latest 2026/2027 -
2026/2027 Official Exam
150 100% 2026/2027
QUESTIONS VERIFIED ANSWERS EDITION
TOPICS COVERED
Module 1: Matter & Measurements Module 4: Chemical Reactions & Stoichiometry
Module 2: Atomic Structure & Periodic Table Module 5: Gases & Solutions
Module 3: Chemical Bonding & Molecular Structure Module 6: Acids, Bases & Equilibrium
COVER PAGE - 1
, SECTION 1 | Matter & Measurements | Q1-Q25 | Chem 103 Module 1 to 6 Exam answers
Portage learning | Graded A+ Latest 2026/2027 - 2026/2027 Official Exam 2026/2027
Q1 Question 1 of 150
A lab technician working in a pharmaceutical quality control lab measures the mass of a white
crystalline powder three times using an analytical balance. The recorded values are 2.341 g, 2.340 g,
and 2.339 g, while the accepted reference value is 2.350 g. Which statement best characterizes
these measurements in terms of accuracy and precision?
A. The measurements demonstrate both high accuracy and high precision
B. The measurements are precise but not accurate
C. The measurements are accurate but not precise
D. The measurements lack both accuracy and precision
Correct Answer: B
Rationale:
The three readings cluster tightly within 0.002 g of each other, confirming high precision since reproducibility is
strong. However, each value deviates from the accepted 2.350 g by roughly 0.010 g, showing systematic error that
reduces accuracy. Precision alone does not guarantee a result is close to the true value.
Q2 Question 2 of 150
A student heats a sample of ice at -10 degrees Celsius in a beaker on a hot plate and records the
temperature every minute. The temperature rises steadily until it reaches 0 degrees Celsius, where it
remains constant for several minutes despite continued heating, then rises again. What physical
change explains the constant-temperature plateau?
A. The ice undergoes sublimation directly into water vapor
B. The ice is absorbing latent heat during the phase change to liquid water
C. The hot plate has automatically reduced its power output
D. The thermometer has reached its calibration limit at 0 degrees
Correct Answer: B
Rationale:
The plateau at 0 degrees Celsius corresponds to the melting point, where added thermal energy breaks
intermolecular bonds rather than increasing kinetic energy. This latent heat of fusion is consumed entirely by the
phase transition, keeping temperature constant. Sublimation would skip the liquid phase entirely, and a hot plate
does not self-regulate in this manner.
Q3 Question 3 of 150
A researcher prepares two samples for analysis: Sample X is a clear, uniform liquid that cannot be
separated by filtration, and Sample Y is a cloudy suspension of fine sand particles in water that
settles over time. How should these two samples be classified in terms of homogeneity?
A. Both X and Y are heterogeneous mixtures
B. Both X and Y are homogeneous mixtures
Chem 103 Module 1 to 6 Exam answers Portage learning | ... | 2026/2027 | Passing Score: 80%% | Page 2
, C. Sample X is homogeneous and Sample Y is heterogeneous
D. Sample X is a pure substance and Sample Y is a mixture
Correct Answer: C
Rationale:
A homogeneous mixture has uniform composition at the molecular level, meaning no visible boundaries between
components, which describes Sample X. Sample Y contains distinct regions of sand and water with visible
separation, making it heterogeneous. Classification depends on visual uniformity and whether components can be
distinguished, not on whether a substance is pure.
Q4 Question 4 of 150
A metallurgist needs to separate a mixture of iron filings, sodium chloride crystals, and small pieces
of sulfur. She first uses a magnet to remove the iron, then adds water to dissolve the salt, filters the
remaining sulfur, and evaporates the filtrate to recover the salt. Which fundamental property of matter
does each separation step exploit?
A. Chemical reactivity of each component with the solvent
B. Differences in physical properties such as magnetism, solubility, and state
C. Differences in the density and melting point of each component
D. The ability of each component to undergo a phase change at room temperature
Correct Answer: B
Rationale:
The magnet separates iron based on its magnetic property, water dissolution exploits the solubility difference of salt
versus sulfur, and filtration relies on the physical state difference between solid sulfur and the liquid filtrate. No
chemical reactions change the identity of any component during these steps. Density separation was not used here,
and not every component undergoes a phase change.
Q5 Question 5 of 150
A chemistry student calculates the density of an irregularly shaped metal object by measuring its
mass as 15.73 g on a balance and determining its volume by water displacement in a graduated
cylinder. The water level rises from 12.5 mL to 17.8 mL when the object is submerged. What is the
density of the metal, expressed with the correct number of significant figures?
A. 2.968 g/mL
B. 2.97 g/mL
C. 3.0 g/mL
D. 2.967 g/mL
Correct Answer: B
Rationale:
The volume by displacement is 17.8 minus 12.5, giving 5.3 mL with two significant figures. Dividing 15.73 g by 5.3
mL yields 2.9679 g/mL, which rounds to 2.97 g/mL to match the two significant figures of the volume measurement.
In multiplication and division, the result is limited to the same number of significant figures as the factor with the
fewest.
Chem 103 Module 1 to 6 Exam answers Portage learning | ... | 2026/2027 | Passing Score: 80%% | Page 3
, Q6 Question 6 of 150
A clinical laboratory reports a patient's blood glucose level as 95 mg/dL. The measurement was taken
using a digital glucometer with a precision of plus or minus 2 mg/dL. If the true glucose concentration
is 97 mg/dL, how should the measurement be described?
A. The measurement is both accurate and precise within the instrument's capability
B. The measurement is precise but the accuracy cannot be determined from this data
C. The measurement is accurate but the precision is unknown without repeated trials
D. The measurement shows a systematic error of 2 mg/dL in the positive direction
Correct Answer: A
Rationale:
A single reading of 95 mg/dL compared to the true value of 97 mg/dL shows a difference of only 2 mg/dL, well within
the instrument's stated precision of plus or minus 2 mg/dL. This small deviation indicates good accuracy, and the
instrument's specification of plus or minus 2 mg/dL defines its precision. Without repeated measurements, precision
is estimated from the manufacturer specification rather than observed reproducibility.
Q7 Question 7 of 150
An environmental scientist measures the temperature of a hot spring at different locations and
records 72.3 degrees Celsius, 71.8 degrees Celsius, 72.1 degrees Celsius, and 71.9 degrees
Celsius. She then converts these readings to Fahrenheit using the correct formula. Which of the
following best represents the proper handling of significant figures in this conversion?
A. Each converted value should retain three significant figures to match the original data
B. The converted values should be rounded to two significant figures because the conversion formula
introduces additional uncertainty
C. The converted values should retain all digits displayed by the calculator for maximum accuracy
D. Significant figure rules do not apply when converting between temperature scales
Correct Answer: A
Rationale:
Temperature conversion between Celsius and Fahrenheit is an exact mathematical operation (multiplication by 9/5
and addition of 32), so no additional uncertainty is introduced. The number of significant figures should be
preserved from the original measurement, meaning three significant figures should be kept. Using fewer figures
discards valid precision, while keeping all calculator digits implies false precision beyond what was measured.
Q8 Question 8 of 150
A first-year chemistry student is asked to express the distance between two atoms in a crystal lattice,
measured as 0.000000342 meters, in proper scientific notation. Which representation follows the
correct scientific notation conventions?
A. 0.342 x 10^-6 m
B. 3.42 x 10^-7 m
C. 34.2 x 10^-8 m
Chem 103 Module 1 to 6 Exam answers Portage learning | ... | 2026/2027 | Passing Score: 80%% | Page 4
2026/2027 Official Exam
OBJECTIVE ASSESSMENT - EXAM
Chem 103 Module 1 to 6 Exam
answers Portage learning |
Graded A+ Latest 2026/2027 -
2026/2027 Official Exam
150 100% 2026/2027
QUESTIONS VERIFIED ANSWERS EDITION
TOPICS COVERED
Module 1: Matter & Measurements Module 4: Chemical Reactions & Stoichiometry
Module 2: Atomic Structure & Periodic Table Module 5: Gases & Solutions
Module 3: Chemical Bonding & Molecular Structure Module 6: Acids, Bases & Equilibrium
COVER PAGE - 1
, SECTION 1 | Matter & Measurements | Q1-Q25 | Chem 103 Module 1 to 6 Exam answers
Portage learning | Graded A+ Latest 2026/2027 - 2026/2027 Official Exam 2026/2027
Q1 Question 1 of 150
A lab technician working in a pharmaceutical quality control lab measures the mass of a white
crystalline powder three times using an analytical balance. The recorded values are 2.341 g, 2.340 g,
and 2.339 g, while the accepted reference value is 2.350 g. Which statement best characterizes
these measurements in terms of accuracy and precision?
A. The measurements demonstrate both high accuracy and high precision
B. The measurements are precise but not accurate
C. The measurements are accurate but not precise
D. The measurements lack both accuracy and precision
Correct Answer: B
Rationale:
The three readings cluster tightly within 0.002 g of each other, confirming high precision since reproducibility is
strong. However, each value deviates from the accepted 2.350 g by roughly 0.010 g, showing systematic error that
reduces accuracy. Precision alone does not guarantee a result is close to the true value.
Q2 Question 2 of 150
A student heats a sample of ice at -10 degrees Celsius in a beaker on a hot plate and records the
temperature every minute. The temperature rises steadily until it reaches 0 degrees Celsius, where it
remains constant for several minutes despite continued heating, then rises again. What physical
change explains the constant-temperature plateau?
A. The ice undergoes sublimation directly into water vapor
B. The ice is absorbing latent heat during the phase change to liquid water
C. The hot plate has automatically reduced its power output
D. The thermometer has reached its calibration limit at 0 degrees
Correct Answer: B
Rationale:
The plateau at 0 degrees Celsius corresponds to the melting point, where added thermal energy breaks
intermolecular bonds rather than increasing kinetic energy. This latent heat of fusion is consumed entirely by the
phase transition, keeping temperature constant. Sublimation would skip the liquid phase entirely, and a hot plate
does not self-regulate in this manner.
Q3 Question 3 of 150
A researcher prepares two samples for analysis: Sample X is a clear, uniform liquid that cannot be
separated by filtration, and Sample Y is a cloudy suspension of fine sand particles in water that
settles over time. How should these two samples be classified in terms of homogeneity?
A. Both X and Y are heterogeneous mixtures
B. Both X and Y are homogeneous mixtures
Chem 103 Module 1 to 6 Exam answers Portage learning | ... | 2026/2027 | Passing Score: 80%% | Page 2
, C. Sample X is homogeneous and Sample Y is heterogeneous
D. Sample X is a pure substance and Sample Y is a mixture
Correct Answer: C
Rationale:
A homogeneous mixture has uniform composition at the molecular level, meaning no visible boundaries between
components, which describes Sample X. Sample Y contains distinct regions of sand and water with visible
separation, making it heterogeneous. Classification depends on visual uniformity and whether components can be
distinguished, not on whether a substance is pure.
Q4 Question 4 of 150
A metallurgist needs to separate a mixture of iron filings, sodium chloride crystals, and small pieces
of sulfur. She first uses a magnet to remove the iron, then adds water to dissolve the salt, filters the
remaining sulfur, and evaporates the filtrate to recover the salt. Which fundamental property of matter
does each separation step exploit?
A. Chemical reactivity of each component with the solvent
B. Differences in physical properties such as magnetism, solubility, and state
C. Differences in the density and melting point of each component
D. The ability of each component to undergo a phase change at room temperature
Correct Answer: B
Rationale:
The magnet separates iron based on its magnetic property, water dissolution exploits the solubility difference of salt
versus sulfur, and filtration relies on the physical state difference between solid sulfur and the liquid filtrate. No
chemical reactions change the identity of any component during these steps. Density separation was not used here,
and not every component undergoes a phase change.
Q5 Question 5 of 150
A chemistry student calculates the density of an irregularly shaped metal object by measuring its
mass as 15.73 g on a balance and determining its volume by water displacement in a graduated
cylinder. The water level rises from 12.5 mL to 17.8 mL when the object is submerged. What is the
density of the metal, expressed with the correct number of significant figures?
A. 2.968 g/mL
B. 2.97 g/mL
C. 3.0 g/mL
D. 2.967 g/mL
Correct Answer: B
Rationale:
The volume by displacement is 17.8 minus 12.5, giving 5.3 mL with two significant figures. Dividing 15.73 g by 5.3
mL yields 2.9679 g/mL, which rounds to 2.97 g/mL to match the two significant figures of the volume measurement.
In multiplication and division, the result is limited to the same number of significant figures as the factor with the
fewest.
Chem 103 Module 1 to 6 Exam answers Portage learning | ... | 2026/2027 | Passing Score: 80%% | Page 3
, Q6 Question 6 of 150
A clinical laboratory reports a patient's blood glucose level as 95 mg/dL. The measurement was taken
using a digital glucometer with a precision of plus or minus 2 mg/dL. If the true glucose concentration
is 97 mg/dL, how should the measurement be described?
A. The measurement is both accurate and precise within the instrument's capability
B. The measurement is precise but the accuracy cannot be determined from this data
C. The measurement is accurate but the precision is unknown without repeated trials
D. The measurement shows a systematic error of 2 mg/dL in the positive direction
Correct Answer: A
Rationale:
A single reading of 95 mg/dL compared to the true value of 97 mg/dL shows a difference of only 2 mg/dL, well within
the instrument's stated precision of plus or minus 2 mg/dL. This small deviation indicates good accuracy, and the
instrument's specification of plus or minus 2 mg/dL defines its precision. Without repeated measurements, precision
is estimated from the manufacturer specification rather than observed reproducibility.
Q7 Question 7 of 150
An environmental scientist measures the temperature of a hot spring at different locations and
records 72.3 degrees Celsius, 71.8 degrees Celsius, 72.1 degrees Celsius, and 71.9 degrees
Celsius. She then converts these readings to Fahrenheit using the correct formula. Which of the
following best represents the proper handling of significant figures in this conversion?
A. Each converted value should retain three significant figures to match the original data
B. The converted values should be rounded to two significant figures because the conversion formula
introduces additional uncertainty
C. The converted values should retain all digits displayed by the calculator for maximum accuracy
D. Significant figure rules do not apply when converting between temperature scales
Correct Answer: A
Rationale:
Temperature conversion between Celsius and Fahrenheit is an exact mathematical operation (multiplication by 9/5
and addition of 32), so no additional uncertainty is introduced. The number of significant figures should be
preserved from the original measurement, meaning three significant figures should be kept. Using fewer figures
discards valid precision, while keeping all calculator digits implies false precision beyond what was measured.
Q8 Question 8 of 150
A first-year chemistry student is asked to express the distance between two atoms in a crystal lattice,
measured as 0.000000342 meters, in proper scientific notation. Which representation follows the
correct scientific notation conventions?
A. 0.342 x 10^-6 m
B. 3.42 x 10^-7 m
C. 34.2 x 10^-8 m
Chem 103 Module 1 to 6 Exam answers Portage learning | ... | 2026/2027 | Passing Score: 80%% | Page 4
