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Fig. 1-To view information on other "Experiments in Electrochemistry," simply click the picture.
Electrochemical Cells - How to Build a Series Battery.
By Caiden F. and Garrett M.

Safety: Always, during every lab, where an apron and a pair of protective goggles.

Before we can even begin to configure a series battery, we must first set-up two (or more) identical cells that resemble the one pictured in Figure 1 (see right) and gather the necessary materials.
Materials (per cell)
:
  • a strip of copper
  • a strip of zinc
  • a large beaker (or suitable container)
  • a porous vase
*acting as a semi-permeable membrane
  • Cupric Sulfate (CuSO4)
  • Zinc Sulfate (ZnSO4)
  • a voltmeter
  • two cables with alligator clips
*more will be needed when the series connection is constructed


Procedure-Setting Up "The Daniell's Cell":
Before beginning, make sure that all equipment being used is sterile.

  1. Begin by taking the large beaker (this can be any size your choice, but this experiment has had successful results with the use of 250 mL beakers) and adding-with the scoopula-Zinc Sulfate. There is not a set amount of (ZnSO4) to be added.
  2. Add distilled water to the (ZnSO4) to create a solution which should fill 1/2 to 3/4 of the large beaker. Stir thoroughly .
  3. In an upright postion, place the strip of zinc into the (ZnSO4) solution. One part should be submerged in the solution while another should be exposed.
  4. Take the porous vase and add, with the scoopula, Copper Sulfate. There is not a set amount of (CuSO4) to be added.
  5. Add distilled water to the (CuSO4) to create a solution which should fill 1/2 to 3/4 of the porous vase. Stir thoroughly.
  6. In an upright postion, place the strip of copper into the (CuSO4) solution. One part should be submerged in the solution while another should be exposed.
  7. Add the porous vase to the (ZnSO4) solution.
  8. Allow for time to pass (more than ten minutes) before going onto step 9.
  9. Using the alligator clips, attach a cable to each exposed end of the metals. Take the "unoccupied" ends of both cables and attach them to a voltmeter.
  10. Record the voltage.
  11. Repeat steps 1-9 to create another (or more) cell(s).
Procedure-Building a Series Battery
To learn how to build a series battery refer to the video below:


BUT WHY DO WE HAVE A VOLTAGE?...HOW DOES THIS WORK? Author Giorgio Carboni answers these questions in "Experiments in Electrochemistry" by stating, "How does the Daniell's Cell work? As we have said, the reactions at the electrodes furnish charges that allow the battery to produce electrical current for extended periods. In the Daniell's Cell, the copper strip attracts electrons from the zinc strip. These electrons pass through the wires of our external circuit. As the copper electrode receives electrons, free positive ions in the solution arrive to equalize the charges. Positive copper ions (Cu++) are attracted to the charged copper electrode where they receive two electrons and become neutral and deposit on the electrode in metallic form. The positive zinc ions (Zn++) move to the porous vase [If we didn't have the porous vase, the Cu++ ions would go directly to the zinc electrode and pick up free electrons, thereby bypassing the external circuit and stopping the current flow through the wires]. For each copper atom that is deposited on the copper electrode, a zinc atom goes into solution, giving up two electrons to the zinc electrode...—These electrons account for the current that is produced..."

WHY IS IT CALLED "THE DANIELL'S CELL?"

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Fig. 2-John Frederic Daniell-Click For an Enlarged View

John Frederic Daniell (1790-1845) was a self-taught chemist whose most important contribution to science was his development of one of the earliest batteries, the Daniell Cell. As Professor of Chemistry at King's College of London, Daniell produced a simple electrical cell (1831) that supplied electricity for a longer time than the the previous Voltaic Cell. Preventing polarization from interrupting the flow of electricity, the set-up isolated copper and zinc ions from each other but also allowed for their interaction through the electrolyte. This movement of ions between the two isolated metals allowed for the electrical circuit. Because of this breakthrough, the growth of the telegraph network was able to continue and Mr. Daniell was awarded the Copley and Royal medals by the Royal Society.

Sources:
http://www.magnet.fsu.edu/education/tutorials/java/daniellcell/index.html
http://www.kcl.ac.uk/college/history/people/daniell.html
http://www.funsci.com/fun3_en/electro/electro.htm
http://www.kcl.ac.uk/depsta/iss/archives/175th/image/f43.jpg