This experiment can be used as a class practical or demonstration. Students learn how to construct a simple lead–acid cell consisting of strips of lead and an electrolyte of dilute sulfuric acid. The cell should then be charged for different lengths of time, before being discharged through a light bulb.
A lead acid cell is an electrochemical cell, comprising of a lead grid as an anode (negative terminal) and a second lead grid coated with lead oxide, as a cathode (positive terminal), immersed in sulfuric acid. The concentration of sulfuric acid in a fully charged auto battery measures a specific gravity of 1.265 – 1.285.
A lead-acid cell is an electrochemical cell, typically, comprising of a lead grid as an anode and a second lead grid coated with lead oxide, as a cathode, immersed in sulfuric acid. The concentration of sulfuric acid in a fully charged auto battery measures a specific gravity of 1.265 – 1.285.
Verify the effect of Temperature on the Cell Potential of the lead acid cell. Verify the effect of Activity (or concentration) of reacting species on the Cell Potential of the lead acid cell. Examine the effect of Electrode Composition on the Cell Potential of the lead acid cell.
The Nernst equation for the lead-acid cell can be written by adding the two half-cell reactions given in equations 1 and 2. Note: The affect of sulfuric acid concentration on the electrode potential, is clearly seen in equation 10, which is a simpler form of equation 9. Using equation 8, the Nernst equation for the lead acid cell is,
The lead electrodes should be cut to size so that they can be folded over the rim of the beaker and the crocodile clips attached, so as to grip the beaker rim and the lead foil together. Care must be taken not to allow the electrodes to touch once the cell is assembled, or for the electrolyte level to bring it into contact with the crocodile clips.