Electrolysis in Aqueous Solutions -- Overvoltage Refer to data from a table of s

Question

Electrolysis in Aqueous Solutions -- Overvoltage

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.

During the electrolysis of an aqueous solution of Na2SO4, which reaction occurs at the (platinum) anode?

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 more than a 2/1 volume ratio of H2(g)/O2(g)
A required potential of less than 1.23 V
The production of sodium hydroxide
The production of H2(g) and O2(g) in the exact volume ratio 2/1

In the electrolysis of brine (chlor-alkali process), which element is produced at the anode?

H2
Cl2
Na
O2

Explanation / Answer

During the electrolysis of an aqueous solution of Na2SO4 the following reaction occurs at anode,
2H2O ---> O2 + 4H+ + 4e-   
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 H2(g) and O2(g) in the exact volume ratio 2/1.
In the electrolysis of brine in chlor-alkali process Cl2 is produced at the anode
At graphite anode the following reaction takes place,
Cl- (aq) ----------> 1/2 Cl2 + e-

Related Questions

Navigate

• Browse (All)
• Browse E
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.