Title: E5 Quiz
Course: Lab Instruments I > Section: E5: Meetings 10,11

Quiz over the objectives for Experiment Set 5.

Q: If substance A gets oxidized while substance B gets reduced in a reaction, which of the following statements is accurate?
- Substance A loses electrons and is the reducing agent. Substance B gains electrons and is the oxidizing agent.
- Substance A loses electrons and is the oxidizing agent. Substance B gains electrons and is the reducing agent.
- Substance A gains electrons and is the reducing agent. Substance B loses electrons and is the oxidizing agent.
- Substance A gains electrons and is the oxidizing agent. Substance B loses electrons and is the reducing agent.
A: Substance A loses electrons and is the reducing agent. Substance B gains electrons and is the oxidizing agent.

Q: Which one of the following statement correctly characterizes oxidation in electrochemical cells?
- Oxidation occurs at the anode in both a galvanic and electrolytic cell.
- Oxidation occurs at the cathode in both a galvanic and electrolytic cell.
- Oxidation occurs at the anode in a galvanic cell and at the cathode in an electrolytic cell.
- Oxidation occurs at the cathode in a galvanic cell and at the anode in an electrolytic cell.
A: Oxidation occurs at the anode in both a galvanic and electrolytic cell.

Q: The Nernst equation relates electrical potential under nonstandard conditions (E) in an electrochemical cell to several factors. Which one of the factors makes the measurement of E useful in analytical chemistry?
- temperature
- concentration (activity) of ions
- standard reduction potential of species involved
- number of electrons transferred in one redox event
A: concentration (activity) of ions

Q: ______ methods utilize a(n) ______cell, which generates a current based on the energy released during a spontaneous redox reaction, whereas ______ methods utilize a(n) ______ cell, which requires the application of a current to provide the energy needed to drive a nonspontaneous reaction.
- Amperometric; electrolytic; potentiometric; galvanic
- Amperometric; galvanic; potentiometric; electrolytic
- Potentiometric; electrolytic; amperometric; galvanic
- Potentiometric; galvanic; amperometric; electrolytic
A: Potentiometric; galvanic; amperometric; electrolytic

Q: Standard conditions are considered the conditions in a laboratory, averaged over a year.
- True
- False
A: False

Q: Electrical potential (voltage) is the cause of current (amperage) in a closed circuit.
- True
- False
A: True

Q: Electroanalytical methods are dependent on the flow of electrons between electrodes.
- True
- False
A: True

Q: A titration that monitors pH is a voltammetric method of analysis.
- True
- False
A: False

Q: A 9-volt battery is an example of a galvanic cell.
- True
- False
A: True

Q: Electrodes should be stored upright in DI water when not in use.
- True
- False
A: False

Q: Which of the following is an indicator electrode?
- Ag-AgCl
- ISE
- SCE
- SHE
A: ISE

Q: Which of the following is NOT utilized in potentiometric analytical methods?
- Auxiliary electrodes
- Combination electrodes
- Indicator electrodes
- Reference electrodes
A: Auxiliary electrodes

Q: Which is FALSE regarding a standard calomel electrode, SCE?
- It is an electrochemical half-cell.
- It contains a saturated solution of KCl.
- It can be the cathode or anode in an electrochemical cell.
- Its potential varies as the concentration of the analyte varies.
A: Its potential varies as the concentration of the analyte varies.

Q: Which one of the following is NOT a purpose of a salt bridge in a reference electrode?
- Facilitate ionic diffusion with the sample solution
- Act as a source of ions to maintain a steady electrical potential
- Provide a means to complete the circuit in the electrochemical cell
- Maintain electrical neutrality within compartments of the electrochemical cell
A: Act as a source of ions to maintain a steady electrical potential

Q: A pH electrode develops a membrane potential. What does this mean?
- Electrical potential is dependent on the difference between the concentration of H+ inside and outside the tip of the electrode.
- Electrical potential is dependent on an acid-base reaction that occurs at the porous interface between the electrode and sample solution.
- Electrical potential is diminished over time due to acid-base half-cell reaction creating a thin coating on the electrode.
- Electrical potential is diminished over time due to H+ in the solution dissolving a thin coating on the tip of the electrode.
A: Electrical potential is dependent on the difference between the concentration of H+ inside and outside the tip of the electrode.