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Electrochemical cells and chemical energy
Basics of electrochemical cell
1) Chemical energy and electrical energy
The copper sulfate and zinc battery is able to supply electrical current that can be used by two-terminal devices like LEDs.
Instead of transforming chemical energy into heat , a copper sulfate and zinc battery converts it into electrical energy.
In an electrochemical cell, chemical energy is converted into electrical energy.
Comment: when one of the reactants has been completely consumed the chemical transformation can not occur and the battery can no longer produce electrical energy. It is said that the battery is discharged.
2) Composition of electrochemical cells
Most of electrochemical cells are comparable to copper sulfate and zinc battery:
There are always two different metals and an electrolyte.
Comment: We define an electrolyte as a medium made conductive by ions it contains
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