AP Chemistry: Electrochemistry 2 ā Questions and Answers
Question 1: In a galvanic cell, oxidation always occurs at which electrode?
- The anode (Correct answer)
- The cathode
- The salt bridge
- The cathode in basic solution only
Correct answer: The anode
Oxidation occurs at the anode in any electrochemical cell.
Question 2: What is the standard cell potential of a cell with EĀ°(cathode) = +0.80 V and EĀ°(anode) = +0.34 V?
- +0.46 V (Correct answer)
- +1.14 V
- -0.46 V
- +0.23 V
Correct answer: +0.46 V
EĀ°cell = EĀ°cathode ā EĀ°anode = 0.80 ā 0.34 = +0.46 V.
Question 3: A positive standard cell potential indicates the reaction is:
- Spontaneous (Correct answer)
- Nonspontaneous
- At equilibrium
- Endothermic
Correct answer: Spontaneous
A positive EĀ°cell corresponds to a negative ĪGĀ°, meaning the reaction is spontaneous.
Question 4: In a salt bridge containing KNOā, which ions migrate toward the anode compartment?
- Anions (NOāā») (Correct answer)
- Cations (Kāŗ)
- Electrons
- Neither ion moves
Correct answer: Anions (NOāā»)
Anions migrate toward the anode to balance the positive charge from oxidation.
Question 5: Which equation relates standard cell potential to the equilibrium constant?
- ĪGĀ° = āRT ln K = ānFEĀ° (Correct answer)
- EĀ° = K/nF
- EĀ° = RT ln(nF)
- K = nFEĀ°/RT
Correct answer: ĪGĀ° = āRT ln K = ānFEĀ°
ĪGĀ° = ānFEĀ° = āRT ln K links cell potential and the equilibrium constant.
Question 6: How many electrons are transferred in the balanced reaction CuĀ²āŗ + 2eā» ā Cu?
- 2 (Correct answer)
- 1
- 3
- 4
Correct answer: 2
Copper(II) gains two electrons to become neutral copper metal.
Question 7: In the cell notation Zn | ZnĀ²āŗ || CuĀ²āŗ | Cu, what does the double vertical line represent?
- The salt bridge (Correct answer)
- The anode
- The voltmeter
- A phase boundary at the electrode
Correct answer: The salt bridge
The double line denotes the salt bridge separating the two half-cells.
AP Chemistry: Electrochemistry 2
In a galvanic cell, oxidation always occurs at which electrode?