Question

Write down the balanced electrode reactions for the electrolysis of water.
4 marks answer please answer ASAP​

Answer 1

Answer:

ANSWER

Electrolysis of water is the decomposition into oxygen and hydrogen gas due to an electric current passed through the water. 

The following equation represents the electrolysis of water :H2O(l) 

In pure water, at the negatively charged cathode, a reduction reaction takes place, with electrons (e−) from the cathode being given to hydrogen cations to form hydrogen gas. 

Reduction at cathode: 2H++2e−→H2 

On positively charged anode, an oxidation reaction occurs, generating oxygen gas by giving electrons to the anode : 

Oxidation at anode: 2H2O→O2(g)+4H+(aq)+4e−

The same half-reactions can also be balanced with the base as listed below. To add half reactions they must be balanced with either acid or base. 

Cathode(reduction)2H2O(l)+2e−→H2(g)+2OH−(aq)Anode (oxidation)4OH−(aq)→O2(g)+2H2O(l)+4e−

Combining either half-reaction pair yields the same overall decomposition of water into oxygen and hydrogen: 

Overall reaction: 2H2O(l)→2H2(g)+O2(g) 

The number of hydrogen molecules produced is thus twice the number of oxygen molecules. The produced hydrogen gas has therefore twice the volume of the produced oxygen gas. The number of electrons pushed through the water is twice the number of generated hydrogen molecules and four times the number of generated oxygen molecules