PORTAGE LEARNING CHEM 104 EXAM SCRIPT
2026 COMPLETE QUESTIONS AND CORRECT
ANSWERS
◉ 8) Which of the half-cell reactions below (A or B) takes place at the
anode in a H2/O2fuel cell?
(A) O2 + 2 H2O + 4e- → 4 OH-
(B) 2 H2 + 4 OH- → 4 H2O + 4e. Answer: (B) 2 H2 + 4 OH- → 4 H2O
+ 4e-
◉ 7) Which of the half-cell reactions below (A or B) takes place at the
cathode in a nickel metal hydride battery?
(A) MH + OH- → M + H2O + e-
(B) NiOOH + H2O + e- → Ni(OH)2 + OH. Answer: (B) NiOOH + H2O
+ e- → Ni(OH)2 + OH-
◉ 6) Which of the half-cell reactions below (A or B) takes place at the
cathode in an alkaline dry-cell battery?
(A) Zn → Zn+2 + 2e-
(B) 2NH4+ + 2MnO2 + 2e- → Mn2O3 + 2NH3 + H2O. Answer: (B)
2NH4+ + 2MnO2 + 2e- → Mn2O3 + 2NH3 + H2O
, ◉ 5) Which of the half-cell reactions below (A or B) takes place at the
anode in a lead-acid battery?
(A) Pb + HSO4- → PbSO4 + H+ + 2e-
(B) PbO2 + HSO4- + 3H+ + 2e- → PbSO4 +2H2O. Answer: (A) Pb +
HSO4- → PbSO4 + H+ + 2e-
◉ 4) In what kind of battery are the reactants fed in, avoiding the
formation of a dead battery? Answer: fuel-cell battery
◉ 3) Why is the lithium ion battery useful for powering cell phones and
laptops? Answer: because it can be charged time and time again
◉ 2) Why is the alkaline dry-cell battery called a primary battery and
what must be done with this battery after discharge? Answer: called
primary because it's unable to be recharged and must be disposed of
◉ 1) Why is the lead-acid battery called a secondary or storage battery?
Answer: Because it is rechargeable
◉ What electrochemical process is the largest consumer of industrial
electricity in North America? Answer: The electrolytic production of
aluminum is the largest consumer of industrial electricity in North
America.
2026 COMPLETE QUESTIONS AND CORRECT
ANSWERS
◉ 8) Which of the half-cell reactions below (A or B) takes place at the
anode in a H2/O2fuel cell?
(A) O2 + 2 H2O + 4e- → 4 OH-
(B) 2 H2 + 4 OH- → 4 H2O + 4e. Answer: (B) 2 H2 + 4 OH- → 4 H2O
+ 4e-
◉ 7) Which of the half-cell reactions below (A or B) takes place at the
cathode in a nickel metal hydride battery?
(A) MH + OH- → M + H2O + e-
(B) NiOOH + H2O + e- → Ni(OH)2 + OH. Answer: (B) NiOOH + H2O
+ e- → Ni(OH)2 + OH-
◉ 6) Which of the half-cell reactions below (A or B) takes place at the
cathode in an alkaline dry-cell battery?
(A) Zn → Zn+2 + 2e-
(B) 2NH4+ + 2MnO2 + 2e- → Mn2O3 + 2NH3 + H2O. Answer: (B)
2NH4+ + 2MnO2 + 2e- → Mn2O3 + 2NH3 + H2O
, ◉ 5) Which of the half-cell reactions below (A or B) takes place at the
anode in a lead-acid battery?
(A) Pb + HSO4- → PbSO4 + H+ + 2e-
(B) PbO2 + HSO4- + 3H+ + 2e- → PbSO4 +2H2O. Answer: (A) Pb +
HSO4- → PbSO4 + H+ + 2e-
◉ 4) In what kind of battery are the reactants fed in, avoiding the
formation of a dead battery? Answer: fuel-cell battery
◉ 3) Why is the lithium ion battery useful for powering cell phones and
laptops? Answer: because it can be charged time and time again
◉ 2) Why is the alkaline dry-cell battery called a primary battery and
what must be done with this battery after discharge? Answer: called
primary because it's unable to be recharged and must be disposed of
◉ 1) Why is the lead-acid battery called a secondary or storage battery?
Answer: Because it is rechargeable
◉ What electrochemical process is the largest consumer of industrial
electricity in North America? Answer: The electrolytic production of
aluminum is the largest consumer of industrial electricity in North
America.
