(Only
for experienced teachers of chemistry!
Sulfuric acid is very corrosive.
Work on a trash.
In Experiment
Me14 you have assembled a lead cell. In the previous
experiment you connected 6 of those lead cells in series to operate
them as one single electrolytical cell .
The result of this chemical reaction was one Galvanic
Cell = Model car battery.
* Test your model car battery
by connecting it to your multimeter.
Observations*
Left:
A voltage of 12.83 V (6 x 2 V) and (right:) a current of 9.23
mA.
Explanation
During
discharging
the following spontaneous indirect redox reaction
takes place:
negative electrode:Pb
---oxidation-->
2e- + Pb2+
positive electrode:2
e- + Pb4+ --reduction-->Pb2+
Chemical reaction during
discharging: PbO2+ Pb + 2
H2SO4--redox-->
2
PbSO4+2 H2O + energy
During recharging
the reverse reactions take place forced by the charging device:
2PbSO4+ 2 H2O + energy --redox-->
PbO2
+
Pb + 2H2SO4