Voltaic Pile

Edit Experiment

VIDEO LINKS:

Lab Experiments (Write protocols and perform experiments based on these):

Data analysis and calculations (Use these if you need help with your data and calculations)

  1. Introduction to electrochemistry:
  2. The electrochemistry experiments:

The prelab must include Experimental Protocol, Chemical Table and Equipment Table.

The lab report requires all sections (including prelab sections) to be completed in one document.

Experimental Protocol

(Analysis) Watch the experiment videos.  Take notes on the protocol.  Stop the video and re-watch as necessary to acquire the details of the procedure.  Write out the protocol for each part of the experiment.  (It can be written in sequential steps.  Complete sentences are not necessary.)  This is the protocol you will follow, so be detailed.

Chemical Table

(Representation) Prepare your chemical table including the materials you will use in the experiment.  Here is a general template that you may use.
Chemical Name Chemical Formula Molar Mass (g/mol) Hazards reference PPE
Sodium Chloride NaCl 58.5 Skin irritation https://fscimage.fishersci.com/msds/21105.htm  
           
           

Equipment Table

(Analysis) Identify the equipment (type AND size) needed for the experiment and include the name and an image of each.  Be sure to describe the equipment, how to use it, and why it is suitable for this use.
Equipment Name Equipment Picture Intended Purpose

Data Collection

(Acquiring competencies) Following your detailed protocol based on the videos, perform all the experiments. Record your observations and take pictures of your key steps in the process.  Your observations and images need to be incorporated in your data section and this section should be as detailed as possible as you will use this information to complete your discussion.

Data Processing

  1. (Representation) Write the half-reaction that occurs at the anode.
  2. (Representation) Write the half-reaction that occurs at the cathode.
  3. (Representation) Write the overall reaction that occurs.
  4. (Existing knowledge, research and views) Present the standard electrode reduction potentials for the half reactions at the anode and cathode.
  5. (Manipulation) Calculate the standard cell potential (E°cell) at 25 ºC using the half-cell potentials.
  6. (Manipulation) Calculate the ΔG° using the ΔG° = - n×F×E°cell.
  7. (Interpretation) Classify your reaction as spontaneous or non-spontaneous.
  8. (Assumptions and Analysis) Fill in the following table using the observations and data from your experiments.
Assumptions made Testing the assumption If assumptions are wrong
The voltaic pile only works with copper and zinc. Combine other metals in similar sequence. There will be current detected.

Discussion

Write a minimum one-page (12 font, single spaced) discussion on the experiment conducted this week. Address at least one question in each category as fully as possible integrating the collected data, providing explanations for the observed trends, and evaluating whether your original assumptions about the experiment were validated by the results. The assignment will be graded on completeness, clarity of the explanations and the meaningful integration of the collected and calculated data. Correct grammar and appropriate format for the chemical formulae and chemical reactions is expected.
  1. Interpretation) Classify the reaction observed in the experiment and provide a supported argument for your choice.
  2. (Existing knowledge, research, and views) Define galvanic cell, electrolytic cell and voltaic cell. Identify your experiment.
  3. (Existing knowledge, research, and views) Define the half-cell, and describe how they work using the experiment as supporting evidence.
  4. (Existing knowledge, research, and views) Describe the relationship between the half-cell potential and the cell potential. Use your experiment as supporting evidence. (Include the units, why some potentials are positive and some negative, and the information gleaned from those numbers.)
  5. (Analysis) Describe the role of the mat board in the pennies experiment. Describe the purpose of the salt and vinegar soak.
  6. (Analysis) The anode and the cathode were separated in each experiment. Provide a supported argument for why they were never in contact with each other during the experiments.
  7. (Existing knowledge, research, and views) Describe what metals are used in the manufacture of the penny and the galvanized nail.
  8. (Existing knowledge, research and views) Compare the sign of the Gibbs free energy of an electrolytic cell to that of a galvanic cell.
  9. (Analysis) Provide a supported argument for not using a battery when making a voltaic cell.
  10. (Assumptions and limitations) Car batteries run at a minimum of 12.6 V. What would have to be true for a potato battery that generates sufficient voltage to replace your car battery? Provide a supported argument for your choice.