What are they?
A voltaic cell is
also known as a galvanic cell, it was named/ created by
Alessandro Volta (voltaic) and Luigi Galvani (galvanic). It is a type
of cell that makes electrical energy from the chemical reactions that
occur inside itself. The chemical reaction that occur inside of the
cell is a redox reaction. Examples: batteries inside your TV
controller, batteries inside flashlight. Examples of types voltaic
cells: 1-Alkaline cell 2-Daniell cell 3-Simple cell 4-Lead-acid
accumulator 5-Dry cell.
The fact that a voltaic cell can produce energy/ electricity is by
using Zinc (anode) and Copper (cathode) that are connected by a wire
and that are put in a solution: CuSO4. When the wire and
the salt bridge (helps to balance the charges in the galvanic cell,
it is composed of Na+Cl- and 2 cotton plugs
that won’t let the solution of Na+Cl- of
pouring into the cathode and anode sites) are there, they will allow
electrons to move through the wire(s) that connect(s) Cu (with a
strong pull of electrons) to Zn (with a weak pull of electrons) with
a LED between the two. When electrons are in a movement position,
they produce or make electricity which will turn the LED on.
We said that there was two chemical reactions: reduction and
oxidation. The cathode (Cu) part is the site where reduction occurs
and the anode is where the oxidation occurs. That because the
electrons are moving from Zn to Cu and the Zn2+ that are
present on the anode site come across to the cathode site and react
with the Cu2+ to make only Cu ? what happens in the
Copper site is a reduction process:
(aqueous = dissolved in water) + 2e- ? Cu (solid metal)
And in the Zinc site is an oxidation process:
(solid)? Zn2+ (aqueous) + 2e-
two half cells
can be called: the reduction half cell and the oxidation half cell.
We saw in TP that if you only put 1 Zn and 1 Cu, it won’t provide
enough electricity to turn a LED on. So what we did is we took more
half lemons and connected the 3 Zn and 3 Cu with 4 more wires and it
made the LED turn on with enough electricity that was moving within
the 4 wires.
An electrolytic cell is also happening with redox reaction. It
is where an electric current will make the transfer of the electrons
during/in the redox reaction. Here, the anode is positively charged
and the cathode is negatively charged. The flow of the electrons
during the redox goes from the positive (anode) to the negative
charge (cathode). The electrolytic cell will convert electrical
energy to chemical energy. A battery is an electrical energy. It is
the total opposite of a galvanic cell.
It is a type of cell that needs energy and is non-spontaneous so
forced. An example of electrolytic cell could be electroplating (it
is the process of coating one metal with another.
Here, the redox occurs in the one and only section, which is where
the anode and the cathode are together so the equations are:
Anode ? oxidation = X- ? X + e
And Cathode ? oxidation = M+ + e ? M
Difference between a voltaic and electrolytic
The Galvanic cell has a salt bridge and the electrolytic doesn’t
2. The Electrolytic cell uses a battery to produce energy and the
Voltaic cell uses a light/ LED.
3. They have a different flow of the electrons: Voltaic ? from
negative (anode) to positive charge (cathode) and Electrolytic ?
form positive (anode) to negative charge (cathode).
4. In Galvanic, the energy goes from the Zinc and the Copper to the
light or LED and in Electrolytic, the energy goes from the battery to
the Zinc and Copper.
5. The voltaic has two sections in two different containers (the
reduction half cell and the oxidation half cell) and the electrolytic
has only one section in one container (redox).
converts chemical energy to electrical power/energy and electrolytic
converts electrical power/energy to chemical energy.
7. Galvanic is a spontaneous and electrolytic is a forced
reaction generates current (galvanic) and a current drives a reaction