The effect of different Electrodes and Electrolytes on voltage
Zinc and copper wet cell batteries produce the highest voltage.
What are electrodes and electrolytes?
An electrode is an electrical conductor connected to a nonmetallic part of a circuit. Electrodes are referred as either the anode or cathode in an electrochemical cell. The anode is the electrode where current leaves the cell and oxidation happens. On the other hand the cathode is where current enters the cell and reduction happens.
An electrolyte is an aqueous type of substance that contains free moving ions. It is the presence of these free moving ions that makes the substance electrically conductive.
Types of electrochemical cells
There are two types of electrochemical cells, galvanic (voltaic) cell and electrolytic cell.
Both cells contain electrodes on which oxidation and reduction happens. However, the cathode and anode are charged differently. In the galvanic (voltaic) cell, the anode is negatively charged and the cathode is positively. It is vice-versa for an electrolytic cell. Here, the anode is positively charged and the cathode is negatively charged.
As such, due to the nature of the anode being negatively charged in the galvanic (voltaic) cell, it provides a ready source of electrons, which are negatively charged. As such, there is spontaneous reaction. In contrast, activity is non spontaneous in an electrolytic cell and in order for the electrolysis reaction to take place, electrical energy is required.
Due to this reason, galvanic (voltaic) cells are commonly used in batteries
However, it is common in both cells, that the anode is the electrode where oxidization occurs and the cathode is where reduction occurs.
A Galvanic (Voltaic) Cell
An Electrolytic Cell
Students should be careful as they are dealing with electricity and chemical reactions in this experiment. Adult supervision required at all times.