1.59C: Write Ionic Half - Equations Representing the Reactions at the Electrodes during Electrolysis and Understand Why These Reactions are Classified as Oxidation or Reduction

ELECTROLYSIS: Decomposition of an ionic substance by passing an electric current through it

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REACTION AT ELECTRODES:

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SOLUTION	PRODUCT AT POSITIVE ELECTRODE	PRODUCT AT NEGATIVE ELECTRODE
LEAD (II) BROMIDE ( PbBr2 )	Bromine   -   Br2 2Br -     -     2e-     →     Br2	Lead   -   Pb Pb2+     +     2e-     →     Pb
SODIUM CHLORIDE ( NaCl )	Chlorine - Cl 2Cl-  -  2e-  →  Cl2	Hydrogen - H2 2H2O  +  2e-  →  H2  +  2OH-
DILUTE SULFURIC ACID ( H2SO4 )	Oxygen - O2 2H2O  -  4e-  →  O2  +  4H+	Hydrogen - H2 2H+  +  2e-  →  H2
COPPER (II) SULFATE ( CuSO4 )	Oxygen - O2 2H2O  -  4e-  →  O2  +  4H+	Copper - Cu Cu2+  +  2e-  →  Cu