faisal shahzad (1) rol num 47

8/10/2019 Faisal Shahzad (1) Rol Num 47

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ROLL NO : F13 E 47ASSIGNMENT OF CHEMISTRY

TOPIC; BASIC CONCEPT OF ELECTROCHEMISTRYSUBMITTED TO

SIR DR. ISRAR AHMAD


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*.Chemistry and electricity*.Electro neutrality

*.Potential differences at interfaces*.References*.concept map*.What you should be able to do..


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Electrochemistry is the branch of chemistry deal with chemicalreaction that involve electrical currents and potentials.

Some chemical reaction that proceed spontaneously can generateelectrical current ,which can be used to do useful work ,while otherchemical reaction can be forced by using electrical current.

Everyday examples of electrochemistry; The best known everyday electrochemistry device maybe the

batteries. the simple thrown away batteries ,which you use in yourflash lights , in many digital cameras etc .are electrochemical cells.these are produced with certain chemical in them ,which will reactwith each other and produced an electrical current as soon as youclose the switch .ones the chemical in cell are all use up the cell isthrown away and a new cell is install in the device .A more sophisticated version off the batteries can be re used over and overagain by recharging with electricity .


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According to Alessandro Volta discovery IN 1973; The connection b/w chemistry and electricity is very old one ,going back to Alessandro Volta

discovery in 1973,that electricity could be produced by placing two moistened paper. In 1800, Nicholson and Carlisle ,using Volta primitive battery as a source , showed that an

electric current could decompose water into oxygen and hydrogen .

This was proof that water is composed of hydrogen and

oxygen . This was surely one of the most significant experiments in in the history of chemistry ,for itimplied that the atom of hydrogen and oxygen were associated with positive and negativeelectric charge, which must be the source of bonding forces b/w them .By 1812,the Swedishchemist Berzelius could propose that all atoms are electrified ,hydrogen and the metal beingpositive , the nonmetals negative .In electrolysis, the applied voltage was thought tooverpower the attraction b/w these opposite charges ,by pulling the electrified atoms apart inthe form of ions. It would be almost exactly a hundred years later before the shared electronpair theory of G.N LEWIS could offer significant improvement over this view of chemical

bonding . Meanwhile the use of electricity as a means of bringing about chemical change continued

to play a central chemical change continued to play a central role in the development ofchemistry .Humphrey Davey prepared the first elemental sodium by electrolysis of asodium hydroxide melt


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Electrochemistry is the branch of chemistry thatstudieschemical reaction which take place in a solution at the interface ofan electron conductor and an ionic conductor .thesereactioninvolve electron transfer b/w the electrode and the electrolyte or

spice in solution . History

Main article ;History of electrochemistry 16thto 18thcenturydevelopments.

German physicist Otto von Guericke beside hiselectrical generator while conducting an experiment.


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Electrochemical reactions are invariably oxidation /reductionreaction carried out under special circumstances. Oxidation is avery well known reaction type. Most people will immediatelythink of rust formation, the reaction of iron with oxygen from theair to produce iron oxide ,rust. But chemist define oxidation in a

much more general way, the reaction with oxygen gas is just oneexample of oxidation.

The general definition of ;;;;

Oxidation/reduction. It is the donation of electron by one molecules or atom to an other.

Thes species that donate the electron is said to be oxidized ,andthe species receiving the electron is said to be reduced .Oxidationand reduction always occur together ,oxidation is alwaysaccompanied by something being reduced, and reduction isalways accompanied by something being oxidized.


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There are numerous other uses of electrochemistry worthmentioning. Electrochemistry is involved in both animal and plantlife. It is balsoinvolve in many aspects of environment protection.Electrochemicalprocesses can also be used to clean and restorearchaeological artifacts. Electrochemistryis widely used toproduces protective oxide coating onseveral metals, primarily onaluminum .It is used in production of some often used electricalcircuit components.


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Table of contents Introduction

Voltaic Cells Galvanic Cells

Cell Potential

Balancing Red ox Reaction

Rules for assigning Oxidation states


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In 1973 ,Alessandro Volta discovered that electricity could beproduced by placing different metal on the opposite sides of a wetpaper or cloth. Hes made his first battery by Ag and Zn on theopposite sides of a moistened cloth with salt or wreak acidsolution .Therefore ,these batteries got the name voltaic cells .

Galvanic cell needs electrical current from outside for it to work.

Notice how there is a voltmeter. Galvanic cell take energy sourcesfrom outside to make itself work.

faisal shahzad (1) rol num 47

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