Seminar Topics & Project Ideas On Computer Science Electronics Electrical Mechanical Engineering Civil MBA Medicine Nursing Science Physics Mathematics Chemistry ppt pdf doc presentation downloads and Abstract

Electro chemistry

[attachment=37039]


Solid lead(II) sulfide reacts with oxygen in the air at high temperatures to form lead(II) oxide and sulfur dioxide. Which substance is a reductant (reducing agent) and which is an oxidant (oxidizing agent)?  
PbS, reductant; O2, oxidant 
PbS, reductant; SO2, oxidant 
Pb2+, reductant; S2- oxidant 
PbS, reductant; no oxidant 
PbS, oxidant; SO2, reductant


Cell Potential


Oxidizing agent pulls the electron.
Reducing agent pushes the electron.
The push or pull (“driving force”) is called the cell potential Ecell
Also called the electromotive force (emf)
Unit is the volt(V)
= 1 joule of work/coulomb of charge
Measured with a voltmeter



Standard Hydrogen Electrode


This is the reference all other oxidations are compared to
Eº = 0
º indicates standard states of 25ºC, 1 atm, 1 M solutions.



Galvanic Cell


The reaction always runs spontaneously in the direction that produced a positive cell potential.
Four things for a complete description.
Cell Potential
Direction of flow
Designation of anode and cathode
Nature of all the components- electrodes and ions