Uploaded by Rudra

Chemistry Project

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12th Grade
Chemistry
Project
VARANASI
PROJECT ON
SESSION 2022 - 23
In successfully completing this
project, many people have helped me.
I would like to thank all those who
are related to this project.
Primarily, I would thank God for
being able to complete this project
with success. Then I will thank our
Principal Mrs. Nirmala Rathore Ma’am
and our teacher Mrs. Harjit Kaur
Ma’am, under whose guidance I
learned a lot about this project. Her
suggestions and directions have
helped in the completion of this
project.
Finally, I would like to thank my
parents and friends who have helped
me with their valuable suggestions
and guidance and have been very
helpful in various stages of project
completion.
CERTIFICATE
This is to certify that
MR. Rudra Pratap Singh
A Students of Class XII-A
Under the Board Roll No…………………………of
GURU NANAK ENGLISH SCHOOL,SHIVPUR
Has satisfactorily completed his
CHEMISRY PROJECT FILE-043
During Academic Session 2022-2023.
Under the guidance of
Mrs. Harjit Mam
Internal Examiner
External Examiner
Table of contents
Sr. No.
Topic
01
Introduction
02
Definition
03
Construction of
Galvanic cell
04
Salt Bridge
05
Mechanism Of
Galvanic cell
06
Representation
of Galvanic cell
07
Daniell cell
08
09
Difference
between
Galvanic and
Electrolytic cell
Bibliography
Introduction
01
Cells and batteries are unquestionably
useful and important. Cells are used in
so many various ways in our daily
lives. A Galvanic Cell or Voltaic Cell is
an electrochemical cell that exists
alongside other cells. It converts the
chemical energy of spontaneous redox
reactions into electrical energy. A
galvanic cell is an example of how
energy can be collected through simple
reactions between a few elements. In
this article, we have discussed
everything about galvanic cells
including galvanic cell definition,
Daniel cell and Leclanche cell .
To facilitate balancing the overall
equation for Galvanic cells and
emphasizing the actual chemical
transformations, it is often
advantageous to divide the oxidationreduction reactions into half-reactions
when formulating the equations. Read
this article to know galvanic cell
definition, construction and more.
Definition
02
A device used to convert chemical
energy produced in a redox reaction
into electrical energy is called a
galvanic cell.
It is named after the name of
scientist Luigi Galvani. Galvani cell is
also called a voltaic cell, named after
the scientist Alessandro Volta.
Some common examples of galvanic
cells are the Volta cell, Daniel cell,
Leclanche cell, dry cell, etc.
03
Construction Of Galvanic Cell
A galvanic cell is constructed by
combining an oxidation electrode
with a suitable reduction electrode
to convert chemical energy into
electrical energy by a redox
reaction. Two electrolytic solutions,
in which electrodes are immersed
are connected to each through a
porous diaphragm or a salt bridge.
The two electrodes are connected
to a device that utilizes the
electrical energy produced in the
outer circuit.
Electrons get liberated i.e.,
oxidation occurs at the oxidation
electrode. These electrons
accumulate on the electrode and
provide a negative potential. At the
reduction electrode, a positive
potential develops on account of
the reduction process occurring at
it.
When these two electrodes are
connected, electrons start flowing
from the oxidation electrode to the
reduction electrode in the outer
circuit due to a difference in
potential between them. Thus, an
electric current is produced.
The electrode at which the
oxidation process occurs is called
the anode, while the one at which
the reduction process takes place is
called the cathode. In a galvanic cell,
the anode has a negative polarity
and the cathode has a positive
polarity.
Salt Bridge
04
A salt bridge is a U- shaped tube
containing a concentrated solution of an
inert electrolyte like KCl, KNO3, K2SO4,
etc., or solidified solution of such an
electrolyte in Agar-Agar and gelatin.
These inert electrolytes do not take part
in the reduction reaction .
The function of the salt bridge is to
allow the movement of ions from one
solution to the other without mixing
two solutions. Thus, whereas electron
flow in the outer circuit in the wire, and
the inner circuit is completed by the
flow of ions from one cell to the other
through the salt bridge. The salt bridge
maintains the electrical neutrality of the
solution in the two half-cells.
05
Mechanism Of Galvanic Cell
The chemical reaction responsible
for the generation of electric current
from chemical energy in a galvanic
cell is a redox reaction. This redox
reaction is called the cell reaction of
the given galvanic cell.
A galvanic cell is composed of two
half cells, i.e., oxidation half cell and
reduction half cell. The oxidation
occurs at the oxidation electrode,
i.e., at the anode, and involves the
liberation of electrons. The
reduction occurs at the reduction
electrode, i.e., at the cathode, and
involves the gain of electrons. The
cell reaction is obtained by adding
oxidation and reduction halfreactions of Daniel cell.
At the anode, oxidation half cell
reaction: Zn→Zn2 + + 2eAt the cathode, reduction half cell
reaction: Cu2 + + 2e-→Cu
The cell reaction (redox
reaction): Zn + Cu2 + →Cu + Zn2 +
Representation Of
Galvanic Cell
06
1. An oxidation and reduction half-cells
are represented by putting a single
vertical line between the symbols of
metal acting as an electrode and the
symbol of ion present in the
electrolyte in contact with metal. The
vertical line represents the phase
boundary.
2. In the oxidation half cell, the reduced
half is written on the left, whereas in
the reduction half cell, the reduced
state is written on the right.
3. The molar concentration of the
solution is written in the parenthesis
after the formula of the ion.
M|Mn+(aq) (Oxidation half)
Mn+(aq)∣M (Reduction half)
4.The salt bridge that connects to the
solution is represented by two parallel
vertical lines, i.e., ǁ.
Example: Cell representation of Daniel
cell Redox reaction occurring in the
Daniel cell is :
Zn+CuSO4→Cu+ZnSO4
Cell representation:
Zn∣∣Zn2+(c1)∥Cu2+(c2)∣∣Cu
Daniell Cell
07
Daniel cell is the best example of a
galvanic cell. The anode of the Daniel
cell consists of a zinc rod dipped in the
solution of zinc sulphate (ZnSO4) of
concentration C1.
The cathode is made by immersing a
copper rod in the solution copper
sulphate (CuSO4) of concentration C2.
The Zn2 + and Cu2+ ions in the
solution are made in electrical
communication either by direct
contact or through a salt bridge.
The zinc electrode acts as an anode at
which oxidation takes place and the
copper electrode acts as a cathode at
which reduction occurs. Since
electrons are produced at the
zinc electrode, this electrode is rich in
electrons and pushes the electron into
the external circuit. Conversely, the
electron-deficient copper electrode
pulls the electron from the external
circuit. Thus, electrons flow from zinc
electrode to copper electrode.
08
Difference between
Galvanic and
Electrolytic cell
Galvanic Cell
Electrolytic Cell
1. It is the device to convert
chemical energy into
electrical energy.
1. It is the device to convert
electrical energy into
chemical energy.
2. In a galvanic cell, the
reaction taking place is
spontaneous.
2. In an electrolytic cell, the
reaction taking place is
non-spontaneous.
3. Two different electrodes
are usually set up in two
separate beakers.
3. Both the electrodes,
either of the same material
or different materials, are
suspended in the
electrolytic solution in the
same beaker.
4. Two different
electrolytes are taken in
two separate beakers.
4. Only one electrolyte is
taken.
5. The electrode on which
oxidation takes place is
called the anode (negative
pole), and the electrode on
which reduction takes place
is the cathode (positive
pole).
5. The electrode which is
connected to the negative
terminal of the battery is
called the cathode, and
reduction occurs here.
Oxidation occurs in the
anode, i.e., the electrode
connected to the positive
terminal.
6. To set this cell, a salt
bridge/porous pot is used.
6. No salt bridge is used in
the electrolytic cell.
7. Free energy change
during the reaction is
negative.
7. Free energy change
during the reaction is
positive.
09
Bibliography

Chemistry Part-1 , Textbook for
class XII

https://www.embibe.com/exams/g
alvanic-cell/

https://www.wikipedia.org/

https://glossary.periodni.com/gloss
ary.php?en=galvanic

https://thesolutionrider.blogspot.co
m/
Thankyou!
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