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.