, CHEM 121 | Module 5 | Original General Chemistry Practice
CHEM 121 Module Exam 5 Portage General
Chemistry w/Lab 100% Correct
1. A student is solving a Module 5 gas problem involving diffusion. Which principle should guide
thesolution?
A) Diffusion can be applied without considering pressure, volume, temperature, or amount.
B) Diffusion has no meaningful relationship to gas behavior.
C) Diffusion is valid only for liquids and solids, not gases.
D) Diffusion is spontaneous mixing and spreading of gas particles through space.
Correct Answer: Diffusion is spontaneous mixing and spreading of gas particles through space.
Rationale: Diffusion is spontaneous mixing and spreading of gas particles through space. Correct setup requires
consistent units and the gas-law relationship that matches the variables held constant or changed.
2. Which statement best describes solve for moles in the study of gases?
A) The ideal gas law can be rearranged as n = PV/RT.
B) Solve For Moles is valid only for liquids and solids, not gases.
C) Solve For Moles can be applied without considering pressure, volume, temperature, or amount.
D) Solve For Moles has no meaningful relationship to gas behavior.
Correct Answer: The ideal gas law can be rearranged as n = PV/RT.
Rationale: The ideal gas law can be rearranged as n = PV/RT. This principle is part of the current CHEM 121 Module 5
gas-law scope.
3. A student is solving a Module 5 gas problem involving kelvin requirement. Which principle
shouldguide the solution?
A) Celsius may always be used directly in gas-law ratios
B) Temperature units cancel even when Celsius is used
C) Gas-law temperature calculations must use absolute temperature in kelvin rather than degrees Celsius.
D) Kelvin is needed only for Boyle's law
Correct Answer: Gas-law temperature calculations must use absolute temperature in kelvin rather than
degrees Celsius.
Rationale: Gas-law temperature calculations must use absolute temperature in kelvin rather than degrees Celsius.
Correct setup requires consistent units and the gas-law relationship that matches the variables held constant or
changed.
4. A student is solving a Module 5 gas problem involving standard conditions comparison.
Whichprinciple should guide the solution?
A) Standard Conditions Comparison can be applied without considering pressure, volume, temperature, or
amount.
B) Standard Conditions Comparison has no meaningful relationship to gas behavior.
C) Standard Conditions Comparison is valid only for liquids and solids, not gases.
D) When comparing gas samples at the same temperature and pressure, equal volumes contain equal
numbers ofmolecules.
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, CHEM 121 | Module 5 | Original General Chemistry Practice
Correct Answer: When comparing gas samples at the same temperature and pressure, equal volumes contain
equal numbers of molecules.
Rationale: When comparing gas samples at the same temperature and pressure, equal volumes contain equal
numbers of molecules. Correct setup requires consistent units and the gas-law relationship that matches the
variables held constant or changed.
5. A student is solving a Module 5 gas problem involving absolute zero extrapolation. Which
principleshould guide the solution?
A) Charles-law behavior extrapolates toward zero volume near 0 K for an idealized gas.
B) Absolute Zero Extrapolation can be applied without considering pressure, volume, temperature, or
amount.
C) Absolute Zero Extrapolation is valid only for liquids and solids, not gases.
D) Absolute Zero Extrapolation has no meaningful relationship to gas behavior.
Correct Answer: Charles-law behavior extrapolates toward zero volume near 0 K for an idealized gas.
Rationale: Charles-law behavior extrapolates toward zero volume near 0 K for an idealized gas. Correct setup
requires consistent units and the gas-law relationship that matches the variables held constant or changed.
6. Which statement best describes mole fraction in the study of gases?
A) Mole Fraction is valid only for liquids and solids, not gases.
B) Mole Fraction has no meaningful relationship to gas behavior.
C) Mole Fraction can be applied without considering pressure, volume, temperature, or amount.
D) Partial pressure can be calculated from mole fraction using Pi = Xi Ptotal.
Correct Answer: Partial pressure can be calculated from mole fraction using Pi = Xi Ptotal.
Rationale: Partial pressure can be calculated from mole fraction using Pi = Xi Ptotal. This principle is part of the
current CHEM 121 Module 5 gas-law scope.
7. What pressure is exerted by 1.00 mol of an ideal gas in 24.6 L at 300 K? Use R=0.08206 L atm mol^-1
K^-1.
A) 1.00 atm
B) 24.6 atm
C) 0.500 atm
D) 2.00 atm
Correct Answer: 1.00 atm
Rationale: P=nRT/V=(1.00 x 0.08206 x 300)/24.6=1.00 atm.
8. Which statement best describes kinetic molecular theory in the study of gases?
A) Ideal gas particles occupy most of the container volume
B) The kinetic-molecular theory models ideal gas particles as tiny, widely separated particles in constant
randommotion with negligible intermolecular attractions.
C) Ideal gas particles remain stationary between collisions
D) Ideal gas particles strongly attract one another
Correct Answer: The kinetic-molecular theory models ideal gas particles as tiny, widely separated particles in
constant random motion with negligible intermolecular attractions.
Page 3
CHEM 121 Module Exam 5 Portage General
Chemistry w/Lab 100% Correct
1. A student is solving a Module 5 gas problem involving diffusion. Which principle should guide
thesolution?
A) Diffusion can be applied without considering pressure, volume, temperature, or amount.
B) Diffusion has no meaningful relationship to gas behavior.
C) Diffusion is valid only for liquids and solids, not gases.
D) Diffusion is spontaneous mixing and spreading of gas particles through space.
Correct Answer: Diffusion is spontaneous mixing and spreading of gas particles through space.
Rationale: Diffusion is spontaneous mixing and spreading of gas particles through space. Correct setup requires
consistent units and the gas-law relationship that matches the variables held constant or changed.
2. Which statement best describes solve for moles in the study of gases?
A) The ideal gas law can be rearranged as n = PV/RT.
B) Solve For Moles is valid only for liquids and solids, not gases.
C) Solve For Moles can be applied without considering pressure, volume, temperature, or amount.
D) Solve For Moles has no meaningful relationship to gas behavior.
Correct Answer: The ideal gas law can be rearranged as n = PV/RT.
Rationale: The ideal gas law can be rearranged as n = PV/RT. This principle is part of the current CHEM 121 Module 5
gas-law scope.
3. A student is solving a Module 5 gas problem involving kelvin requirement. Which principle
shouldguide the solution?
A) Celsius may always be used directly in gas-law ratios
B) Temperature units cancel even when Celsius is used
C) Gas-law temperature calculations must use absolute temperature in kelvin rather than degrees Celsius.
D) Kelvin is needed only for Boyle's law
Correct Answer: Gas-law temperature calculations must use absolute temperature in kelvin rather than
degrees Celsius.
Rationale: Gas-law temperature calculations must use absolute temperature in kelvin rather than degrees Celsius.
Correct setup requires consistent units and the gas-law relationship that matches the variables held constant or
changed.
4. A student is solving a Module 5 gas problem involving standard conditions comparison.
Whichprinciple should guide the solution?
A) Standard Conditions Comparison can be applied without considering pressure, volume, temperature, or
amount.
B) Standard Conditions Comparison has no meaningful relationship to gas behavior.
C) Standard Conditions Comparison is valid only for liquids and solids, not gases.
D) When comparing gas samples at the same temperature and pressure, equal volumes contain equal
numbers ofmolecules.
Page 2
, CHEM 121 | Module 5 | Original General Chemistry Practice
Correct Answer: When comparing gas samples at the same temperature and pressure, equal volumes contain
equal numbers of molecules.
Rationale: When comparing gas samples at the same temperature and pressure, equal volumes contain equal
numbers of molecules. Correct setup requires consistent units and the gas-law relationship that matches the
variables held constant or changed.
5. A student is solving a Module 5 gas problem involving absolute zero extrapolation. Which
principleshould guide the solution?
A) Charles-law behavior extrapolates toward zero volume near 0 K for an idealized gas.
B) Absolute Zero Extrapolation can be applied without considering pressure, volume, temperature, or
amount.
C) Absolute Zero Extrapolation is valid only for liquids and solids, not gases.
D) Absolute Zero Extrapolation has no meaningful relationship to gas behavior.
Correct Answer: Charles-law behavior extrapolates toward zero volume near 0 K for an idealized gas.
Rationale: Charles-law behavior extrapolates toward zero volume near 0 K for an idealized gas. Correct setup
requires consistent units and the gas-law relationship that matches the variables held constant or changed.
6. Which statement best describes mole fraction in the study of gases?
A) Mole Fraction is valid only for liquids and solids, not gases.
B) Mole Fraction has no meaningful relationship to gas behavior.
C) Mole Fraction can be applied without considering pressure, volume, temperature, or amount.
D) Partial pressure can be calculated from mole fraction using Pi = Xi Ptotal.
Correct Answer: Partial pressure can be calculated from mole fraction using Pi = Xi Ptotal.
Rationale: Partial pressure can be calculated from mole fraction using Pi = Xi Ptotal. This principle is part of the
current CHEM 121 Module 5 gas-law scope.
7. What pressure is exerted by 1.00 mol of an ideal gas in 24.6 L at 300 K? Use R=0.08206 L atm mol^-1
K^-1.
A) 1.00 atm
B) 24.6 atm
C) 0.500 atm
D) 2.00 atm
Correct Answer: 1.00 atm
Rationale: P=nRT/V=(1.00 x 0.08206 x 300)/24.6=1.00 atm.
8. Which statement best describes kinetic molecular theory in the study of gases?
A) Ideal gas particles occupy most of the container volume
B) The kinetic-molecular theory models ideal gas particles as tiny, widely separated particles in constant
randommotion with negligible intermolecular attractions.
C) Ideal gas particles remain stationary between collisions
D) Ideal gas particles strongly attract one another
Correct Answer: The kinetic-molecular theory models ideal gas particles as tiny, widely separated particles in
constant random motion with negligible intermolecular attractions.
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