Standard Cell Notation (line notation) - PSAU

Standard Cell Notation (line notation) Conventions: Anode on Left Single line : represent phase boundaries Two line : represent liquid junction e- V e- Zn Zn2+

Cu Cu2+ NO3- NO3 - Anode / anode solution // cathode solution / Cathode Example:

Zn / Zn2+ (1.0 M) // Cu2+ (1.0M) / Cu Line Notation solidAqueousAqueoussolid

Anode on the leftCathode on the right Single line different phases. Double line porous disk or salt bridge. If all the substances on one side are aqueous, a platinum electrode is indicated. For the last reaction Cu(s)Cu+2(aq)Fe+2(aq),Fe+3(aq)Pt(s) Cu

2+ Fe+2 17_360 e e e e Porous disk

Oxidation e (a) Reducing agent Anode Reduction Oxidizing agent

(b) e Cathode Copyright McGraw-Hill 2009 7 Practice: In a galvanic cell, the electrode that acts as a source of electrons to the solution is called

the __________; the chemical change that occurs at this electrode is called________. a. cathode, oxidation b. anode, reduction c. anode, oxidation d. cathode, reduction Practice Under standard conditions, which of the following is the net reaction that occurs in the cell? Cd|Cd2+ || Cu2+|Cu a. Cu2+ + Cd Cu + Cd2+ b. Cu + Cd Cu2+ + Cd2+

c. Cu2+ + Cd2+ Cu + Cd d. Cu + Cd 2+ Cd + Cu2+ Galvanic Cell 1. 2. 3. 4. 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 Oxidation Numbers on the Periodic Table Cell Potential Cell Potential / Electromotive Force (EMF): The pull or driving force on electrons Measured voltage (potential difference)

The total cell potential is the sum of the potential at each electrode. 17_363 e e Zn(s) e e Ecell = +1.10 V

+ Zn 2 SO 4 2 1.0 M Zn 2 solution Anode + Cu 2 SO 4 2 +

1.0 M Cu solution 2+ Cathode Cu(s) E0cell Cell Potential, E0cell

cell potential under standard conditions elements in standard states (298 K) solutions: 1 M gases: 1 atm Practice Completely describe the galvanic cell based on the following half-reactions under standard conditions. MnO4- + 8 H+ +5e- Mn+2 + 4H2O E=1.51 V Fe+3 +3e- Fe(s)

E=0.036V