Portage Learning CHEM 104 Module 2 Exam | General Chemistry II w/ Lab (2026) Actual Q&A PDF

CHEM 104 Module 2 | General Chemistry II w/ Lab Exam
Q&A | Portage Learning
These are original practice questions written for study. They are not official CHEM
104, Portage Learning, or university exam questions and are not copied from any
copyrighted question bank. They cover common CHEM 104 Module 2 | Chemical
Equilibrium topics: equilibrium constants, Le Chatelier’s principle, reaction quotient,
ICE tables, Ksp, Ka/Kb, pH, buffers, and titrations.



Question 1:
A nurse is reviewing arterial blood gas results. Which principle best explains why CO₂
levels affect blood pH?
A. Equilibrium shifts in the bicarbonate buffer system
B. CO₂ is a strong base
C. CO₂ has no effect on pH
D. CO₂ increases oxygen saturation

Correct answer: A
Rationale: CO₂ reacts with water to form carbonic acid, shifting the bicarbonate
equilibrium and lowering pH.



Question 2:
At chemical equilibrium:
A. The reaction has stopped
B. Forward and reverse rates are equal
C. All reactants are consumed
D. Only products are present

Correct answer: B
Rationale: Equilibrium is dynamic; forward and reverse reaction rates are equal.



Question 3:
Which statement about equilibrium is correct?
A. Concentrations remain constant at equilibrium
B. Concentrations are always equal
C. The reaction goes to completion
D. No products form

,Correct answer: A
Rationale: At equilibrium, concentrations remain constant but are not necessarily
equal.



Question 4:
For the reaction N₂(g) + 3H₂(g) ⇌ 2NH₃(g), the equilibrium constant expression is:
A. K = [NH₃]² / ([N₂][H₂]³)
B. K = [N₂][H₂]³ / [NH₃]²
C. K = [NH₃] / ([N₂][H₂])
D. K = [N₂][H₂] / [NH₃]

Correct answer: A
Rationale: K = products^coefficients / reactants^coefficients.



Question 5:
For the reaction 2SO₂(g) + O₂(g) ⇌ 2SO₃(g), the equilibrium constant expression is:
A. K = [SO₃]² / ([SO₂]²[O₂])
B. K = [SO₂]²[O₂] / [SO₃]²
C. K = [SO₃] / ([SO₂][O₂])
D. K = [SO₂][O₂] / [SO₃]

Correct answer: A
Rationale: K = [SO₃]² / ([SO₂]²[O₂]).



Question 6:
Which species are NOT included in equilibrium constant expressions?
A. Gases
B. Aqueous ions
C. Pure solids and liquids
D. Weak acids

Correct answer: C
Rationale: Pure solids and pure liquids have constant activity and are omitted from K
expressions.



Question 7:
For the reaction CaCO₃(s) ⇌ CaO(s) + CO₂(g), the equilibrium constant expression is:
A. K = [CO₂]
B. K = [CaO][CO₂] / [CaCO₃]

, C. K = [CaCO₃] / ([CaO][CO₂])
D. K = [CaO] / [CaCO₃]

Correct answer: A
Rationale: Solids are omitted, so K = [CO₂].



Question 8:
If K >> 1, the reaction favors:
A. Reactants
B. Products
C. Neither
D. Equal amounts

Correct answer: B
Rationale: Large K means products are favored at equilibrium.



Question 9:
If K << 1, the reaction favors:
A. Reactants
B. Products
C. Neither
D. Equal amounts

Correct answer: A
Rationale: Small K means reactants are favored at equilibrium.



Question 10:
If K = 1, at equilibrium:
A. Reactants are favored
B. Products are favored
C. Reactants and products are comparable
D. No reaction occurs

Correct answer: C
Rationale: K = 1 means products and reactants are present in comparable amounts.



Question 11:
The reaction quotient Q is calculated:
A. At any point in time