14.3.1 Electrolysis of Aqueous Solutions

• What type of energy is used to drive a non-spontaneous chemical reaction in electrolysis?

  Electrical energy
• In electrolysis, an electric current is passed through an electrolyte
• The electrolyte in electrolysis must be a solution or molten compound that conducts electricity.
• Match the components of the electrolysis of water with their corresponding products:

  Cathode ↔️ Hydrogen gas

  Anode ↔️ Oxygen gas
• Arrange the components of an electrolytic cell in their order of function:

  1️⃣ Electric power supply

  2️⃣ Electrolyte

  3️⃣ Anode

  4️⃣ Cathode
• What is the charge of the anode in an electrolytic cell?

  Positive
• The anode in an electrolytic cell is where oxidation occurs.
• Reduction occurs at the cathode in an electrolytic cell.
• Match the electrode with its process and electron activity:

  Anode ↔️ Oxidation, loses electrons

  Cathode ↔️ Reduction, gains electrons
• What are the products of electrolyzing molten sodium chloride ($NaCl$)?


  Sodium metal and chlorine gas
• In electrolysis, oxidation involves the loss of electrons.
• What is the charge of the electrode where oxidation occurs?

  Positive
• The reaction $A \rightarrow A^{ + } +$$e^{ - }$ represents oxidation at the anode.
• Match the process with its definition and electron activity:

  Oxidation ↔️ Loss of electrons

  Reduction ↔️ Gain of electrons
• What determines the products of electrolysis in aqueous solutions?

  Discharge preference of ions
• Cations with lower reduction potential are more likely to be reduced.
• In electrolysis, $Br^{ - }$ ions are oxidized before $OH^{ - }$ ions because they have a higher oxidation potential.
• What gas is produced at the cathode when electrolyzing concentrated NaCl solution?

  Hydrogen gas
• The reaction at the anode in the electrolysis of concentrated NaCl solution is 2Cl^{ - } \rightarrow Cl_{2} + 2e^{ - }</latex>, which produces chlorine gas.
• Match the electrode with its charge and process:

  Anode ↔️ Positive, oxidation

  Cathode ↔️ Negative, reduction
• What is the role of the anode in an electrolytic cell?

  Oxidation
• The cathode in an electrolytic cell is the negative
• An electrolyte in an electrolytic cell must contain ions to conduct electricity
• What provides the energy to drive electrolysis in an electrolytic cell?

  Electric power supply
• Match the electrode with its properties:

  Anode ↔️ Positive charge, oxidation

  Cathode ↔️ Negative charge, reduction
• In the electrolysis of molten $NaCl$, which ion is reduced at the cathode?


  $Na^{ + }$
• Oxidation involves the loss of electrons
• Reduction always occurs at the cathode in electrolysis
• In the electrolysis of $NaCl$, what gas is formed at the anode?


  Cl_{2}</latex>
• Cations with lower reduction potential are more likely to be discharged at the cathode
• Anions with higher oxidation potential are more likely to be discharged at the anode
• What gas is produced at the cathode during the electrolysis of concentrated $NaCl$ solution?


  $H_{2}$
• An active electrode participates in the chemical reaction by being oxidized or reduced
• What is an example of an inert electrode in electrolysis?

  Platinum
• Steps to calculate cell potential

  1️⃣ Identify the oxidation and reduction half-reactions

  2️⃣ Find the standard electrode potentials for each half-reaction

  3️⃣ Use the formula $E^{°}_{cell} =$$E^{°}_{reduction} - E^{°}_{oxidation}$
• What is the cell potential for a cell with $Cu^{2 + } / Cu$ andZn^{2 + }/Zn</latex> half-cells?


  $+$$1.10 V$
• Electrolysis uses electrical energy to drive a non-spontaneous
• Write the balanced equation for the electrolysis of water.

  2H_{2}O(l) \rightarrow 2H_{2}(g) + O_{2}(g)</latex>
• What is the cell potential for the given electrochemical cell?

  + 1.10 V
• Electrolysis is the process of using electrical energy to force a non-spontaneous chemical reaction.