ConceptConceptDocsDocuments

AP Chemistry 9.9: Cell Potential and Free Energy

Practice AP Chemistry questions on calculating standard cell potential from half-reactions and relating its sign to ΔG° and favorability.

Syllabus
Effective Fall 2025
Course
AP Chemistry

Exam points

  • Calculate standard cell potential from oxidation and reduction half-reaction potentials with correct signs.
  • Write balanced overall redox equations, identify electrons transferred, and use stoichiometry with cell potentials.
  • Relate cell-potential sign to thermodynamic favorability and calculate ΔG° = −nFE° with correct units.

9.9.A—Explain whether an electrochemical cell is thermodynamically favored, based on its standard cell potential and… question 1

[Maximum number: 1]

A scientist constructs a galvanic cell as shown in the diagram. As the cell operates, the Zn(s)\mathrm{Zn}(s)

electrode increases in mass and the Al(s)\mathrm{Al}(s) electrode decreases in mass. A data table with the

standard reduction potentials for the substances follows the diagram.

Figure for Question 9.9.A—Explain whether an electrochemical cell is thermodynamically favored, based on its standard cell potential and… question 1 — AP Chemistry
Table for Question 9.9.A—Explain whether an electrochemical cell is thermodynamically favored, based on its standard cell potential and… question 1 — AP Chemistry
Table for Question 9.9.A—Explain whether an electrochemical cell is thermodynamically favored, based on its standard cell potential and… question 1 — AP Chemistry

The standard Zn/Al cell has a value of Ecell ∘E_{\text {cell }}^{\circ} equal to 0.90 V. The scientist needs a galvanic cell

that produces a greater voltage. The scientist has access to the chemical systems in the table.

If the scientist uses the Zn half-cell and one of the other options from the table, what is the

MAXIMUM voltage that could be generated at standard conditions?

All question bank results loaded