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Electrolysis question

  1. Nov 6, 2009 #1
    1. The problem statement, all variables and given/known data
    Why does electrolysis of molten NaCl yield sodium and chlorine, while electrolysis of a solution of NaCl in water yields sodium hydroxide and chlorine.

    2. Relevant equations

    3. The attempt at a solution
    Is it because H+ is more readily reduced than Na+?

    2H+ + 2e --> H2 Eo= 0
    2Cl- --> Cl2 + 2e Eo=-1.358

    Thus, 2H+ + 2Cl- --> Cl2 H2 Eorxn=-1.358 V

    And so 2H+ --> H2, leaving OH- behind in place of Cl-
     
    Last edited: Nov 7, 2009
  2. jcsd
  3. Nov 7, 2009 #2

    Borek

    User Avatar

    Staff: Mentor

    Any ideas? You see, that template that you should use is not a joke, but a tool to force you follow forum rules.

    --
    methods
     
  4. Nov 7, 2009 #3
    Is it because H+ is more readily reduced than Na+?

    2H+ + 2e --> H2 Eo= 0
    2Cl- --> Cl2 + 2e Eo=-1.358

    Thus, 2H+ + 2Cl- --> Cl2 H2 Eorxn=-1.358 V

    And so 2H+ --> H2, leaving OH- behind in place of Cl-
     
    Last edited: Nov 7, 2009
  5. Nov 7, 2009 #4

    Borek

    User Avatar

    Staff: Mentor

    Yes. Note that further discussion is irrelevant, as you should compare reduction potentials of H+ and Na+, chlorine reaction doesn't change.

    --
    methods
     
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