We come across many things in our daily life that is related to electrochemical reactions directly or indirectly. Flashlight, batteries are to start with involve electrochemical reactions and uses the principle of an electrochemical cell. Can you name a few more modern-day gadgets where an electrochemical cell or Daniel cell forms the principle? It is named Daniel Cell after the British chemist and meteorologist “John Frederic Daniell” who invented it in the year 1836. An electrochemical/Daniel/ Voltaic cell is related to electrode potential. How? Let us find out in this chapter.
Galvanic/ Voltaic Cell
It is an electrochemical cell that uses redox reaction or redox process to produce electrical energy/electricity. Refer to the diagram below…show more content… This is because zinc is higher in the activity series in comparison to copper. Therefore, zinc is oxidized more easily than copper.
Zn (s) → Zn2+ + 2e−
The electrode where oxidation takes place is called anode. In this case, zinc anode slowly depreciates due to loss of zinc metal while the cell operates. Thus, the concentration of zinc ion will gradually increase because of electron generation at the anode. Therefore, it is the negative electrode.
The electron moves from zinc anode through the external wire and continues towards the copper electrode. As a result, voltmeter registers a reading.
Finally, the electrons will enter the copper electron and combine with copper ions present in the solution to form the metallic copper.
Cu2+ (aq) + 2e–→ Cu(s)
The reduction takes place in the copper electrode. It is also called a cathode. Gradually the mass of cathode will increase because of the formation of copper metal. However, the half-cell concentration of the copper (II) ions will decrease. Thus, cathode acts as a positive…show more content… This process will not even require an actual construction of the cell. The half-cell having the higher reduction potential as per the table will undergo reduction process in the particular cell. Similarly, the half-cell having lower reduction potential will undergo oxidation process inside the particular cell. Following the specifications, the determination of overall cell potential is possible. It will always be a positive value otherwise the redox reaction will not be spontaneous. The negative cell potential indicates that the reaction will be spontaneous but in reverse