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Through exhaustive experimentation, the charge of a single electron has been determined to be 1 . 602 × 10 19 size 12{1 "." "602" times "10" rSup { size 8{ - "19"} } } {} coulombs (C). (The coulomb charge unit–defined as useful for much larger charged objects–is inconvenient for expressing such a small charge, so other electrical charge units are commonly used.) One mole of electrons has a total charge calculated to be 96,485 C; this quality is defined as faraday (F):

  1 F = 96,485 C/mol e size 12{"1 F"="96,485 C/mol e" rSup { size 8{ - {}} } } {}

 Electric currents (l) are measured in amperes (A), amps for short, and defined in terms

I = Q/t

1 A = 1 C/s

 For example, a constant current of .600 A (milliamperes) over a period of 2 . 00 × 10 2 size 12{2 "." "00" times "10" rSup { size 8{2} } } {} seconds represents

Q = I × 5 = 0 . 600 A × 200s = 0 . 600 C/s × 200s = 120 C size 12{Q=I times 5=0 "." "600 A" times "200s"=0 "." "600 C/s" times "200s"="120 C"} {}

a movement of 120 coulombs. The number of moles of electrons (n) transported during the time interval is

= 1 . 24 × 10 2 mol e 1 size 12{ {}=1 "." "24" times "10" rSup { size 8{ - 2} } "mol e" rSup { size 8{ - 1} } } {}

Time intervals measured in minutes and hours must be converted to seconds in such calculations. Another useful equation in Electrochemistry is Ohm's Law, where:V = I R where V is the potential difference in volts, I is the current in amperes and R is a constant, measured in ohms, called the resistance.

Experimental procedure



CAUTION The 6 M nitric acid used in the next step will burn and stain the skin as well as damage clothing. In case of skin or clothing contact, wash the area immediately with large amounts of water.

  • Obtain a piece of copper foil (about 2 cm × 8 cm size 12{"2 cm" times "8 cm"} {} ). Holding the foil with tweezers or tongs, dip it into 6 M nitric acid several times until its surface is bright and shiny. Do not allow tweezers or tongs to touch the acid solution. Rinse the foil in de-ionized water and set it aside. This is the anode. Set the nitric acid aside to use in the electroplating exercise.
  • Obtain a piece of copper mesh (about 5 cm × 8 cm size 12{"5 cm" times "8 cm"} {} ) and remove any loose pieces of copper. Clean and rinse it as in step 1. Place the copper mesh on a watch glass in the drying oven. Be careful not to touch the cleaned surfaces. This is the cathode.
  • Add 350 mL 1.0 M KNO 3 size 12{"KNO" rSub { size 8{3} } } {} solution to a 400 mL beaker.

 CAUTION The copper sulfate used in the next step is toxic. Avoid skin contact

  • To this solution, add about 5 mL of 1 M H 2 SO 4 size 12{H rSub { size 8{2} } "SO" rSub { size 8{4} } } {} and 10 g of CuSO 4 5H 2 O size 12{"CuSO" rSub { size 8{4} } cdot "5H" rSub { size 8{2} } O} {} . Stir until the copper sulfate pentahydrate is fully dissolved.
  • Assemble the apparatus shown in Figure 1, but leave the copper mesh electrode in the oven. Add a magnetic stirring bar to the beaker. If necessary, add additional 1.0 M KNO 3 size 12{"KNO" rSub { size 8{3} } } {} to bring solution level in the beaker within 2 cm of the rim. You will either measure the electric directly with an ammeter in series with the electrolytic cell or you will measure the current indirectly by measuring the voltage across a resistor of known value (about 10 ohms).
  • Remove the copper mesh electrode from the oven, let it cool, and determine its mass to the nearest milligram.
  • Attach the copper mesh electrode to the negative terminal of your power supply using an alligator clip. Turn on the magnetic stirrer.
  • Turn on the low voltage power supply and adjust the current until about 140 mA are flowing through the cell. Record the time and current.
  • Record the time and current every five minutes for an hour.
  • After the last reading, gently remove the cathode from the solution while yet attached to the power supply. After the copper mesh has cleared the solution, remove the wire and turn off the power supply.
  • Gently dip-rinse the copper mesh electrode several times in a beaker of deionized water, and place it on a watch glass in the drying oven.
  • When dry, remove the electrode from the oven and let it cool. Reweigh the mesh electrode.
  • Remove the magnetic stirring bar from your beaker and dispose of the solution in the sink.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
Nasa has use it in the 60's, copper as water purification in the moon travel.
nanocopper obvius
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
analytical skills graphene is prepared to kill any type viruses .
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
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Source:  OpenStax, Gen chem lab. OpenStax CNX. Oct 12, 2009 Download for free at http://cnx.org/content/col10452/1.51
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