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Author Topic: what is the connection between salt water and bleach?  (Read 12067 times)

Offline Hadrian

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Can you explain the connection between salt water and bleach?


 

Offline lightarrow

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Re: what is the connection between salt water and bleach?
« Reply #1 on: 08/12/2006 14:31:08 »
You can make bleach NaClO, in these 2 ways, for example:
 
1) Add chlorine Cl2 to sodium hydroxide NaOH. Bleach and kitchen salt (NaCl) is formed:

2NaOH + Cl2 → NaClO + NaCl + H2O

2) By electrolysis of salt water:

At the + electrode (Anode): 2Cl- → Cl2 +  2e-

At the - electrode (Cathode): 2Na+ + 2e- → 2Na;      2Na + 2H2O → 2NaOH + H2

The gaseous hydrogen H2 leaves the solution, the gaseous chlorine Cl2 dissolves in it and react with NaOH according to the first equation I wrote.
« Last Edit: 12/12/2006 18:18:24 by chris »
 

Offline eric l

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Re: what is the connection between salt water and bleach?
« Reply #2 on: 08/12/2006 18:21:11 »
Actually, industrial electrolysis of salt uses either a diaphragm to separate the chlorine from the solution or a mercury cathode to dissolve The sodium if you do not want to end up with bleach !
 

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Re: what is the connection between salt water and bleach?
« Reply #2 on: 08/12/2006 18:21:11 »

 

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