12-Redox_2_web - The IUPAC convention: write both half...

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Ox(1) reacts with Red(2) to yield Red(1) and Ox(2):    (1) Ox(1) + n e Red(1)   (1)   (2) Ox(2) + n e Red(2)   (2)   Ox(1)     + Red(2) Ox(2)     + Red(1)   where  n  is  the  number  of  electrons  exchanged.  Conjugate redox systems. The  IUPAC  convention:  write  both  half  reactions  as  reduction reactions. Two redox reactions: To  obtain  the  net  reaction,  reaction  (2)  should  be  subtracted  from reaction (1). 
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 Cell half-reaction (half-cells) are written as reduction  reactions  Activities of reaction components are unity (standard  conditions)  The potentials are referred to the universal standard, the  Normal Hydrogen Electrode (NHE)  Other convenient reference electrodes: calomel electrode  or silver/silver chloride electrode  High positive potential values indicate a strong tendency  for accepting electrons  A higher positive potential of a given half-cell with respect  to another indicates that the former has stronger oxidizing  properties than the latter In the Standard Electrode Potential Table:
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The electrode at which oxidation (of the solution  reducing agent) occurs is called anode, and at which  reduction occurs is called cathode.  The cathode accepts electrons and the anode donates  electrons if the reaction is made to occur. A cell should be written with the anode on the left, and  cathode on the right. anode / solution / cathode or, in so called “line notation”: (anode)  Pt Fe(C 1 ),Fe(C 2 )  Ce(C 3 )Ce(C 4 )  Pt (cathode)  More About Electrochemical Cells 
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The single vertical line represents a phase boundary,  that is, the boundary between either the solid  electrode and a solution or between two solutions.   C's are concentrations (activities, when needed).   The double line stands for the salt bridge (liquid  junction).  The calculated cell voltage is: E o  = E o (cathode) - E o (anode) (anode)  Pt Fe(C 1 ),Fe(C 2 )  Ce(C 3 )Ce(C 4 )  Pt (cathode) 
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12-Redox_2_web - The IUPAC convention: write both half...

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