Products of electrolysis of sodium chloride. (1 Viewer)

[sikeveo]

Does anyone have the results for this prac? I seem to be missing the results =/

identify data, plan and perform a first-hand investigation to identify the products of the electrolysis of sodium chloride

 

[pravski]

for concentrated sodium chloride

Cathode:
Water gets reduced (can't remember the exact eqn but its in the table of standard potentials)

Anode:
Water gets oxidised (check table again)
Chlorine gets oxidised 2Cl- <--> 2Cl + 2e-

 

[~Smurfette~]

Here's basically what I have down for that dot point:
In industry, sodium hydroxide is manufactured by the electrolysis of salt water (brine). Hydrogen and chlorine gas are also produced.

Reaction at the cathode:
Na+(aq) + e- >< Na(s) (note: this is only for molten NaCl)
2H2O(l) + 2e- >< H2(g) + OH-(aq)

Hydrogen gas is released rather than sodium, which thereby combines with the hydroxide ion to form sodium hydroxide.

Reaction at the anode:
2Cl-(aq) ><M Cl2(g) + 2e-

Overall reaction: 2NaCl(aq) + 2H2O(l) >< 2NaOH(aq) + Cl2(g) + H2(g)
Ionic equation: 2Na+(aq) + 2Cl-(aq) + H2O(l) >< 2Na+ + 2OH-(aq) + Cl2(g) + H2(g)
Net ionic equation: 2Cl-(aq) + 2H2O(l) >< Cl2(g) + H2(g) + 2)H-(aq)