Chemistry 30 (2015)

Inquiry Based Cell Comparison Lab

Abstract:

Create a complete summary of your lab, including a summarized purpose, procedure, results and errors.

Background:

  • Completely explain a voltaic cell (including specific examples and equations)
  • Completely explain an electrolytic cell (including specific examples and equations)

*** make sure your background has sources within it ***

Objectives:

  1. to become familiar with the construction and operation of electrochemical cells
  2. to predict the reactions and voltages that should result
  3. to construct electrochemical cells and measure their voltages

Purpose

  • Create a voltaic cell and electrolytic cell out of household materials.
  • You will be provided with 1 metallic solution to assist your set up, all other materials must be provided by your group of 4.

Variables:

Controlled – minimum 5 controlled variables

Manipulated – 1 manipulated variable

Responding – minimum 3 responding variables

Materials and Procedure:

  • In your group, create a materials list including specific amounts,
  • In your group, create a step by step procedure, in past tense, including specific amounts.

*** make sure your procedure has sources within it ***

Diagrams:

  • Include a diagram of both cells you created. Include amounts in your diagrams and a proper title for your diagrams.
  • Include all labels (including substances as well as technical name)
  • SOA, SRA, Anode, Cathode, Reduction and Oxidation

Analysis of Results

  1. Write the equations for the following
  1. anode half reaction
  2. cathode half reaction
  3. overall cell reaction
  4. calculate the theoretical standard state cell voltage (where possible)
  1. Explain how your results supported the fact that your cell was voltaic or electrolytic (how did you know?)
  1. If your cells were successful, explain how you knew they were successful (what results supported or proved that you have a voltaic or electrolytic cell)
  2. If your cell was not successful, explain how you knew it was not successful and how to make it more successful (DO NOT USE ERRORS IN THIS EXPLANATION)

*** make sure your analysis has sources within it ***

Conclusion:

Create a complete conclusion including results and a list of 3 errors you will describe in your error analysis.

Extension:

  1. Photosynthesis (plant and algae producers) and Cellular Respiration (in plants and animals
  2. Corrosion of metals and Electrochemical strategies to avoid Corrosion (ie sacrificial anode / galvanization)
  3. Electrorefining of Metals (Zinc, Copper, etc) from ores and Electroplating of Metals
  4. Paper Making and Photography

Choose one of the above topics for your extension, and complete the following information.

  • In depth description of what the process is, where it occurs and how it happens
  • In depth chemical analysis of the redox reaction (diagram and description) SHOWING ELECTRON TRANSFER
  • Uses in life or in industry; how this process is useful to people in general
  • Determination on whether this Reaction is more like a voltaic or electrolytic cell and a quick summary of what each is justifying your choice on whether it is like a voltaic or electrolytic cell.

*** make sure your extension has sources within it ***

Error Analysis:

Include minimum 3 errors that are not fixable by redoing the lab or fixing things you forgot to do.

Sources:

Minimum 10 sources for this lab.

Follow Up Questions

  1. Design and draw a diagram of an electrochemical cell that has a magnesium anode and a theoretical standard state voltage of 3.17V. Provide the cell composition and show the half reactions, net equation and cell potential calculation. Also determine whether this cell is electrolytic or voltaic and explain why. (5 marks)
  1. Explain why you should not expect an electrochemical cell to operate for an unlimited period of time (2 mark)

*Lab Report will be marked on the Science Lab Report Rubric*

Cell Rubric (in addition to lab report)

6 / 4 / 2 / 0
Voltaic Cell / Cell was successfully demonstrated, with appropriate materials and analysis / Cell was successfully demonstrated however difficult to understand and/or materials were not appropriate and/or analysis was not applicable / Cell was constructed unsuccessfully.
Cell was not constructed. Digital analysis was provided as an alternative. / Cell was not constructed and no digital analysis was applied to learning.
Electrolytic Cell / Cell was successfully demonstrated, with appropriate materials and analysis / Cell was successfully demonstrated however difficult to understand and/or materials were not appropriate and/or analysis was not applicable / Cell was constructed unsuccessfully.
Cell was not constructed. Digital analysis was provided as an alternative. / Cell was not constructed and no digital analysis was applied to learning.