Refer to data from a table of standard reduction potentials for common half-reac
ID: 1060007 • Letter: R
Question
Refer to data from a table of standard reduction potentials for common half-reactions and/or the following half-reaction to answer the questions below.
1.) During the electrolysis of an aqueous solution of Na2SO4, which reaction occurs at the (platinum) cathode?
2.) During the electrolysis of water containing 0.01 M sodium sulfate, using platinum electrodes, the overvoltage for the oxidation of water results in:
A required potential of greater than 1.23 V
A required potential of exactly 1.23 V
The production of sodium hydroxide
The production of slightly less than a 2/1 volume ratio of H2(g)/O2(g)
3.) In the electrolysis of brine (chlor-alkali process), which element is produced at the anode?
Cl2
Na
O2
H2
Explanation / Answer
1) During the electrolysis of an aqueous solution of Na2SO4, this reaction occurs at the (platinum) cathode.
2H2O + 2e- ----> H2 + 2OH-
2) During the electrolysis of water containing 0.01 M sodium sulfate, using platinum electrodes, the overvoltage for the oxidation of water results in:-
The production of slightly less than a 2/1 volume ratio of H2(g)/O2(g)
3.) In the electrolysis of brine (chlor-alkali process), H2is produced at the anode