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• What is the first step in setting up an electrochemical cell?

  Clean copper and zinc with emery paper

  
• Why is it important to clean the metal pieces?

  It removes the oxide layer on the metal
• What is used to degrease the metal pieces?

  Cotton wool and propanone
• Why is degreasing necessary for the electrochemical cell?

  Grease could prevent efficient cell operation
• What solution is placed with the copper in the beaker?

  1.0 mol dm​-3 CuSO​4​ solution
• What does the copper solution represent in the setup?

  It is a half-cell
• What solution is placed with the zinc in the beaker?

  1.0 mol dm​-3 ZnSO​4​ solution
• What does the zinc solution represent in the setup?

  It is a half-cell
• What is used to connect the two beakers in the setup?

  A plastic U-tube
• What is the purpose of the U-tube in the electrochemical cell?

  To connect the two half-cells
• What must be ensured about the ends of the U-tube?

  They must be fully submerged in solutions
• Why is a voltmeter included in the circuit?

  To read off the voltage of the cell
• What do salt bridges allow in an electrochemical cell?

  Movement of ions between electrodes
• What is a requirement for the salt bridge material?

  It must not react with the electrolyte
• What is often used as a salt bridge material?

  Platinum
• What alternative can be used instead of a U-tube for a salt bridge?

  A strip of filter paper saturated with NaCl
• What is the first step in comparing electrode potentials of different metals?

  Clean a piece of copper with emery paper

  
• What is connected to the positive terminal of the voltmeter?

  A crocodile clip attached to copper
• What is placed on top of the copper during the comparison?

  A moistened piece of filter paper
• What is the purpose of the second lead connected to the voltmeter?

  To connect to a different metal
• What should be recorded when measuring voltage?

  The voltage reading, including the sign
• What can the cell potential be during measurements?

  It can be positive or negative
• What should be done after measuring the voltage with different metals?

  Compare the electrode potentials

  
• What are the steps to set up an electrochemical cell?

  1. Clean copper and zinc with emery paper.
  2. Degrease with cotton wool and propanone.
  3. Place copper in CuSO​4​ solution.
  4. Place zinc in ZnSO​4​ solution.
  5. Connect with a U-tube filled with NaCl.
  6. Connect metals with crocodile clips and voltmeter.

  
• What are the functions of a salt bridge in an electrochemical cell?

  • Allows movement of ions between electrodes
  • Completes the circuit
  • Must be inert and conduct electricity
• What are the steps to compare electrode potentials of different metals?

  1. Clean a piece of copper.
  2. Connect to voltmeter with crocodile clip.
  3. Moisten filter paper with NaCl and place on copper.
  4. Connect a different metal to voltmeter.
  5. Record voltage reading, including the sign.
  6. Repeat with different metals.