Electrolysis

• What is the purpose of electrolysis?

  To break down compounds using electricity
• What compounds are being examined in the experiment?

  Copper chloride and sodium sulfate
• How much liquid should be filled in the beaker for the experiment?

  15 centimeters cubed
• What should be ensured about the electrodes during the experiment?

  They must be submerged but not too close to clips
• What voltage is recommended for this practical experiment?

  4 volts
• What is the role of the red wire in the experiment?

  It connects to the positive terminal (anode)
• What is expected to happen when the circuit is turned on?

  A reaction will take place with chemical formation
• How long should the experiment run to observe the reaction?

  About five minutes
• What ions are present in copper chloride?

  Copper ions (Cu²⁺) and chloride ions (Cl^-)
• What is observed at the positive electrode during electrolysis of copper chloride?

  Bubbles indicating gas formation
• How can chlorine ions be tested during the experiment?

  By holding blue litmus paper above the anode
• What happens to the litmus paper when chlorine is present?

  It gets bleached
• What forms at the cathode during the electrolysis of copper chloride?

  Copper metal
• What is produced at the anode during the electrolysis of copper chloride?

  Chlorine gas
• What is the process called where chloride ions are oxidized to chlorine gas?

  Oxidation reaction
• What happens to copper ions at the cathode?

  They are reduced to copper metal
• What are the half equations for the electrolysis of copper chloride?

  • At the anode: 2Cl^- → Cl₂ + 2e^- (oxidation)
  • At the cathode: Cu²⁺ + 2e^- → Cu (reduction)
• Why is sodium sulfate tested in the experiment?

  It contains a more reactive metal than hydrogen
• What is observed at both electrodes during the electrolysis of sodium sulfate?

  Bubbles forming at both electrodes
• What gas is formed at the negative electrode during sodium sulfate electrolysis?

  Hydrogen gas
• What gas is formed at the anode during sodium sulfate electrolysis?

  Oxygen gas
• What is the source of oxygen gas formed at the anode during sodium sulfate electrolysis?

  From hydroxide ions in water
• What reaction occurs at the anode involving hydroxide ions?

  Oxidation reaction producing oxygen gas
• What additional product is formed during oxidation reactions involving hydroxide ions?

  Water
• How do you balance the charges in the electrolysis equations?

  Ensure equal negative charges on both sides
• What is the significance of balancing both elements and charges in half equations?

  To ensure conservation of mass and charge