14.1.1 Standard Electrode Potentials

• An electrochemical cell converts chemical energy into electrical energy through redox reactions
• The standard electrode potential (SEP) is measured under standard conditions
• What is the standard temperature for measuring SEP?

  298 K
• The standard pressure for measuring SEP is 101 kPa.
• The standard concentration for measuring SEP is 1 M
• What does a higher SEP indicate about a metal's tendency?

  Stronger tendency to be reduced
• The half-cell reaction $Zn^{2 + }(aq) +$$2e^ - \rightarrow Zn(s)$ has $E° =$$- 0.76 V$, indicating a tendency for zinc to be oxidized
• The salt bridge in an electrochemical cell balances the charge buildup between half-cells.
• In a Daniell cell, which electrode acts as the cathode?

  Copper electrode
• The reduction reaction at the cathode in a Daniell cell is $Cu^{2 + }(aq) +$$2e^ - \rightarrow Cu(s)$, where copper ions are reduced
• Arrange the steps in the operation of an electrochemical cell in a logical order.

  1️⃣ Electrons are released at the anode

  2️⃣ Electrons flow through the external circuit

  3️⃣ Ions in the electrolyte carry charge

  4️⃣ Electrons are accepted at the cathode

  5️⃣ Charge is balanced by the salt bridge
• Match the components of an electrochemical cell with their functions:

  Electrodes ↔️ Redox reaction sites

  Electrolyte ↔️ Enables charge flow
• What is the standard temperature in Kelvin for measuring SEP?

  298 K
• The standard pressure for measuring SEP is 101 kPa.
• A higher SEP indicates a stronger tendency to be reduced.
• Match the components of an electrochemical cell with example materials:

  Electrodes ↔️ Copper, Zinc

  Electrolyte ↔️ CuSO₄, ZnSO₄

  Salt Bridge ↔️ KCl
• What is the role of electrodes in an electrochemical cell?

  Conduct electrons
• The electrolyte in an electrochemical cell provides ions to facilitate the flow of charge
• A salt bridge balances the charge buildup in an electrochemical cell.
• What are the electrodes in a Daniell cell?

  Copper and zinc
• In a Daniell cell, copper sulfate and zinc sulfate solutions serve as the electrolyte
• Oxidation always occurs at the anode in an electrochemical cell.
• What is the role of electrolytes in maintaining charge neutrality within an electrochemical cell?

  Provide ions
• The standard hydrogen electrode (SHE) operates under a temperature of 298 K and a pressure of 101 kPa
• The half-cell reaction in SHE involves hydrogen gas and hydrochloric acid.
• What is one advantage of using the standard hydrogen electrode (SHE)?

  Reliable reference point
• One disadvantage of the standard hydrogen electrode (SHE) is that it is difficult to maintain standard conditions
• Steps to determine the standard electrode potential (SEP) using SHE

  1️⃣ Set up the electrochemical cell

  2️⃣ Measure the cell potential

  3️⃣ Calculate the standard electrode potential
• What is the standard electrode potential of the SHE?

  0 V
• The formula to calculate the standard electrode potential of a cell is $E°_{cell} =$$E°_{cathode} - E°_{anode}$ where $E°_{SHE} =$$0$ V
• The standard electrode potential is measured under standard conditions, including 298 K temperature and 1 M concentration.
• What does a higher standard electrode potential indicate?

  Stronger tendency to be reduced
• The half-cell reaction $Zn^{2 + }(aq) +$$2e^ - \rightarrow Zn(s)$ has a standard electrode potential of $E° =$$- 0.76$ V
• Match the electrochemical cell component with its example material:

  Electrodes ↔️ Copper, Zinc

  Electrolyte ↔️ CuSO₄, ZnSO₄

  Salt Bridge ↔️ KCl
• Order the components of a Daniell cell from anode to cathode:

  1️⃣ Zinc electrode

  2️⃣ Zinc sulfate solution

  3️⃣ Salt bridge

  4️⃣ Copper sulfate solution

  5️⃣ Copper electrode
• Electrolytes ensure redox reactions can proceed continuously in an electrochemical cell.
• Why is the standard hydrogen electrode (SHE) used as a reference electrode?

  To compare electrode potentials
• What occurs at the anode in an electrochemical cell?

  Oxidation
• Electrons are consumed at the cathode
• Electrolytes ensure charge neutrality in electrochemical cells