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really stuck on sodium chloride dot poiint (1 Viewer)

sanshi

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hey
i was wondering if anyone could help me with the following dotpoint as i dont think we covered it in school as our teacher was away
*perform a first hand investigation to identify the products of the electrolysis of sodium chlroide
*analyse information form secondary sources to predict and explain the different products of electrolysis of aqueous andf molten sodium chloride
any help would be greatly appreciated :)
 

pathum

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• Analyse information from secondary sources to predict and explain the different products of the electrolysis of aqueous and molten sodium chloride
Dilute Aqueous
Cathode: 2 possibilities
2H2O(l) + 2e- * H2(g) + 2OH-(aq) (Eo= -0.83V)
Or
Na+(aq) + e- * Na(s) (Eo= -2.71V)
H2O is a stronger oxidant than Na+
Therefore
2H2O(l) + 2e- * H2(g) + 2OH-(aq)
Anode: 2H2O(l) * O2(g) + 4H+(aq) + 4e-

• Analyse information from secondary sources to predict and explain the different products of the electrolysis of aqueous and molten sodium chloride
Dilute Aqueous
Cathode: 2 possibilities
2H2O(l) + 2e- * H2(g) + 2OH-(aq) (Eo= -0.83V)
Or
Na+(aq) + e- * Na(s) (Eo= -2.71V)
H2O is a stronger oxidant than Na+
Therefore
2H2O(l) + 2e- * H2(g) + 2OH-(aq)
Anode: 2H2O(l) * O2(g) + 4H+(aq) + 4e-

Concentrated Aqueous
Cathode: same as before
Anode: 2 possibilities
2H2O(l) * O2(g) + 4H+(aq) + 4e- (Eo= -1.23V)
Or
2Cl- * Cl2(g) + 2e- (Eo= -1.40V)
Both reactions occur at intermediate concentrations. More concentrate NaCl solutions produce greater combinations of chlorine gas.

Molten
Cathode: Na+ + e- * Na(l)
Anode: 2Cl- * Cl2(g) + 2e-

These were by Yvette Law 2005 found in the resources section, sorry i dont have time to type my own. If u need further help just reply and im happy to assist! Goodluck!
 

speedie

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what about the first one?
*perform a first hand investigation to identify the products of the electrolysis of sodium chlroide
 

lloydicles

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speedie said:
what about the first one?
*perform a first hand investigation to identify the products of the electrolysis of sodium chlroide
Products include:
  • NaOH (Sodium Hydroxide) - test with phenolthailene (spelt that one wrong lol)
  • Hydrogen gas test by adding soap to the cell and burning the bubbles over the anode (it makes a loud pop)
  • Chlorine gas (test by the smell of a pool - but really strong - oh and the inability to breath, i.e. death)
has to be done in a well-ventilated area!!
cholrine wont kill for a while but stilll...

i liked this prac, its one of the few that gets really difinitive results!!
(btw, we're a bit behind on our option - only 2 weeks of school left and we havent even started section three of the syllabus lol
 

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