Daniel cell
Introduction
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Electrochemistry refers to the conversion of chemical energy to electrical energy and vice versa . It is basically the study of Production of electricity from energy released during spontaneous reaction and use of electrical energy to bring about non-spontaneous chemical transformation .
A spontaneous chemical reaction is a reaction which happens on its own and releases free energy . This reaction produces electric energy from chemical reaction . For example , burning of coal , rusting of iron , melting of ice , etc .
On the other hand non-spontaneous reaction occurs by providing an external source like electricity . For example , Hydrolysis of water .
o Electrochemistry is used for the following purposes .
o Production of metals like sodium hydroxide , chlorine , fluorine and many other chemicals .
o It is also used for purification of metals .
o The process is used in batteries as well as fuel cells which converts the chemical energy into electrical energy and is used in several instruments and devices . o This process is used in electroplating .
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The reactions carried out using the process of electrochemistry are energy effective and less polluting .
Daniel cell
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The cell that converts the chemical energy liberated as a result of redox reaction to electrical energy is called a Daniel cell .
o It has an electrical potential of 1.1 V . o The setup for Daniel cell is as follows :
o In a beaker a plate of zinc is dipped in a solution of zinc sulphate ( ZnSO4 ).
o In another beaker a plate of copper is dipped in a solution of copper ( II ) sulphate in another container . These plates of metal are called the electrodes of the cell .