Exam: Portage Learning CHEM 103 General
Chemistry I Module 3 Exam | 2026/2027 Updated
Edition with 100% Verified Answers
Q1 What is the definition of an exothermic reaction?
What is the definition of an exothermic reaction?
A) A reaction that absorbs heat from the surroundings
B) A reaction that releases heat into the surroundings CORRECT
C) A reaction where the temperature of the system decreases
D) A reaction where ΔH is positive
Rationale
Exothermic reactions release energy, usually as heat, and have a negative enthalpy change (ΔH < 0).
Q2 According to Boyle’s Law
According to Boyle’s Law, what happens to the volume of a gas when the pressure is doubled at
constant temperature?
A) The volume doubles
B) The volume is reduced by half CORRECT
C) The volume stays the same
D) The volume quadruples
Rationale
Boyle’s Law states pressure and volume are inversely proportional (P₁V₁ = P₂V₂). Doubling pressure
halves the volume.
Q3 What is the standard molar volume of an ideal gas at STP?
What is the standard molar volume of an ideal gas at STP?
A) 1.00 L
Page 1
,B) 22.4 L CORRECT
C) 24.5 L
D) 0.0821 L
Rationale
At STP (0°C and 1 atm), one mole of any ideal gas occupies 22.4 liters.
Q4 Which gas law describes the relationship between volume and temperature of a...
Which gas law describes the relationship between volume and temperature of a gas at constant
pressure?
A) Boyle’s Law
B) Charles’s Law CORRECT
C) Gay-Lussac’s Law
D) Dalton’s Law
Rationale
Charles’s Law states volume is directly proportional to absolute temperature (V₁/T₁ = V₂/T₂) at constant
pressure.
Q5 What is the specific heat equation used to calculate heat transfer?
What is the specific heat equation used to calculate heat transfer?
A) q = m × c × ΔT CORRECT
B) q = m × c × ΔT
C) q = m × ΔT
D) q = c × ΔT
Rationale
The heat equation q = mcΔT relates heat (q) to mass (m), specific heat (c), and temperature change
(ΔT).
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,Q6 In the Ideal Gas Law equation PV = nRT
In the Ideal Gas Law equation PV = nRT, what does the variable ‘n’ represent?
A) Number of particles
B) Number of moles CORRECT
C) Number of grams
D) Number of atoms
Rationale
In the Ideal Gas Law, ‘n’ represents the amount of substance in moles.
Q7 Calculate the heat required to raise the temperature of 10.0 g of water by...
Calculate the heat required to raise the temperature of 10.0 g of water by 5.0°C. (c of water = 4.184
J/g°C)
A) 41.84 J
B) 209.2 J CORRECT
C) 50.0 J
D) 4.184 J
Rationale
q = m × c × ΔT = 10.0 g × 4.184 J/g°C × 5.0°C = 209.2 J.
Q8 What happens to the pressure of a gas in a rigid container if the temperature...
What happens to the pressure of a gas in a rigid container if the temperature is increased?
A) Pressure decreases
B) Pressure increases CORRECT
C) Pressure remains constant
D) Volume increases
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, Rationale
Gay-Lussac’s Law states pressure is directly proportional to absolute temperature at constant volume
(P₁/T₁ = P₂/T₂).
Q9 What is Dalton’s Law of Partial Pressures?
What is Dalton’s Law of Partial Pressures?
A) The average of all individual pressures
B) The product of all individual pressures
C) The sum of the partial pressures of all component gases CORRECT
D) Equal to the pressure of the most abundant gas
Rationale
Dalton’s Law states total pressure equals the sum of partial pressures of each gas in a mixture.
Q10 Show the calculation of the final temperature for an 18.5 g piece of copper...
Show the calculation of the final temperature for an 18.5 g piece of copper heated to 100°C added
to 45.2 g of water at 23.2°C in a coffee cup calorimeter. (c water = 4.184 J/g°C; c Cu = 0.384 J/g°C)
A) 24.5°C
B) 25.3°C CORRECT
C) 26.1°C
D) 27.0°C
Rationale
Heat lost by copper = heat gained by water. 18.5 × 0.384 × (100 - Tf) = 45.2 × 4.184 × (Tf - 23.2). Solve
for Tf ≈ 25.3°C.
Q11 How much energy is involved in condensation of 165 g of steam at 100°C? (Heat...
How much energy is involved in condensation of 165 g of steam at 100°C? (Heat of Vaporization
for water = 2.26 kJ/g)
A) 165 kJ
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Chemistry I Module 3 Exam | 2026/2027 Updated
Edition with 100% Verified Answers
Q1 What is the definition of an exothermic reaction?
What is the definition of an exothermic reaction?
A) A reaction that absorbs heat from the surroundings
B) A reaction that releases heat into the surroundings CORRECT
C) A reaction where the temperature of the system decreases
D) A reaction where ΔH is positive
Rationale
Exothermic reactions release energy, usually as heat, and have a negative enthalpy change (ΔH < 0).
Q2 According to Boyle’s Law
According to Boyle’s Law, what happens to the volume of a gas when the pressure is doubled at
constant temperature?
A) The volume doubles
B) The volume is reduced by half CORRECT
C) The volume stays the same
D) The volume quadruples
Rationale
Boyle’s Law states pressure and volume are inversely proportional (P₁V₁ = P₂V₂). Doubling pressure
halves the volume.
Q3 What is the standard molar volume of an ideal gas at STP?
What is the standard molar volume of an ideal gas at STP?
A) 1.00 L
Page 1
,B) 22.4 L CORRECT
C) 24.5 L
D) 0.0821 L
Rationale
At STP (0°C and 1 atm), one mole of any ideal gas occupies 22.4 liters.
Q4 Which gas law describes the relationship between volume and temperature of a...
Which gas law describes the relationship between volume and temperature of a gas at constant
pressure?
A) Boyle’s Law
B) Charles’s Law CORRECT
C) Gay-Lussac’s Law
D) Dalton’s Law
Rationale
Charles’s Law states volume is directly proportional to absolute temperature (V₁/T₁ = V₂/T₂) at constant
pressure.
Q5 What is the specific heat equation used to calculate heat transfer?
What is the specific heat equation used to calculate heat transfer?
A) q = m × c × ΔT CORRECT
B) q = m × c × ΔT
C) q = m × ΔT
D) q = c × ΔT
Rationale
The heat equation q = mcΔT relates heat (q) to mass (m), specific heat (c), and temperature change
(ΔT).
Page 2
,Q6 In the Ideal Gas Law equation PV = nRT
In the Ideal Gas Law equation PV = nRT, what does the variable ‘n’ represent?
A) Number of particles
B) Number of moles CORRECT
C) Number of grams
D) Number of atoms
Rationale
In the Ideal Gas Law, ‘n’ represents the amount of substance in moles.
Q7 Calculate the heat required to raise the temperature of 10.0 g of water by...
Calculate the heat required to raise the temperature of 10.0 g of water by 5.0°C. (c of water = 4.184
J/g°C)
A) 41.84 J
B) 209.2 J CORRECT
C) 50.0 J
D) 4.184 J
Rationale
q = m × c × ΔT = 10.0 g × 4.184 J/g°C × 5.0°C = 209.2 J.
Q8 What happens to the pressure of a gas in a rigid container if the temperature...
What happens to the pressure of a gas in a rigid container if the temperature is increased?
A) Pressure decreases
B) Pressure increases CORRECT
C) Pressure remains constant
D) Volume increases
Page 3
, Rationale
Gay-Lussac’s Law states pressure is directly proportional to absolute temperature at constant volume
(P₁/T₁ = P₂/T₂).
Q9 What is Dalton’s Law of Partial Pressures?
What is Dalton’s Law of Partial Pressures?
A) The average of all individual pressures
B) The product of all individual pressures
C) The sum of the partial pressures of all component gases CORRECT
D) Equal to the pressure of the most abundant gas
Rationale
Dalton’s Law states total pressure equals the sum of partial pressures of each gas in a mixture.
Q10 Show the calculation of the final temperature for an 18.5 g piece of copper...
Show the calculation of the final temperature for an 18.5 g piece of copper heated to 100°C added
to 45.2 g of water at 23.2°C in a coffee cup calorimeter. (c water = 4.184 J/g°C; c Cu = 0.384 J/g°C)
A) 24.5°C
B) 25.3°C CORRECT
C) 26.1°C
D) 27.0°C
Rationale
Heat lost by copper = heat gained by water. 18.5 × 0.384 × (100 - Tf) = 45.2 × 4.184 × (Tf - 23.2). Solve
for Tf ≈ 25.3°C.
Q11 How much energy is involved in condensation of 165 g of steam at 100°C? (Heat...
How much energy is involved in condensation of 165 g of steam at 100°C? (Heat of Vaporization
for water = 2.26 kJ/g)
A) 165 kJ
Page 4
