What is electrochemical cell in chemistry

 Electrochemical Cell in Chemistry


An electrochemical cell is a device that converts chemical energy into electrical energy, or electrical energy into chemical energy, through redox (oxidation-reduction) reactions.



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Types of Electrochemical Cells


There are two main types:


1. Galvanic Cell (Voltaic Cell)


Converts chemical energy to electrical energy.


Spontaneous redox reaction occurs.


Used in batteries.



Example: Daniel Cell (Zinc-Copper cell)


2. Electrolytic Cell


Converts electrical energy to chemical energy.


Non-spontaneous redox reaction occurs by applying external electricity.


Used in electroplating, electrolysis of water.




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Basic Parts of an Electrochemical Cell


1. Electrodes:


Anode: Oxidation occurs here.


Cathode: Reduction occurs here.




2. Electrolyte:


Solution that conducts electricity by movement of ions.




3. Salt Bridge (in Galvanic cells):


Maintains electrical neutrality by allowing ion flow between two half-cells.




4. External Circuit:


Electrons flow from anode to cathode.






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Example: Daniel Cell (Galvanic Cell)


Anode (Zn):

Zn → Zn²⁺ + 2e⁻ (Oxidation)


Cathode (Cu):

Cu²⁺ + 2e⁻ → Cu (Reduction)



Electrons flow from zinc to copper, generating current.



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Let me know if you want a labeled diagram or a Hindi explanation.



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