useful products from electrolysis of brine

electrolysis of brine

soloution of NaCl(aq) produces chlorine hydrogen and sodium hydroxide when electrolysed

reactions at each electrode for brine

chloride ions react at the positive electrode(anode) to form chlorine gas 2Cl-(aq) —> Cl2(g)+2E-

each chloride ion has lost an electron so the reaction is oxidation

hydrogen ions from the water react at the negative electrode cathode to form hydrogen gas 2H+(aq) +2e- —> H2(g)

each hydrogen ion has gained an lectron so the reaction is reduction

the remaining sodium ions and hydroxide ions stay in soloution forming sodium hydroxide soloution

Diaphragm cell

prevents what going thru

Has a diaphragm dividing the cells.

its porous as it allows brine to pass from one side to other but prevents chlorine and hydrogen gas from passing through.

pro and con of diaphragm cell

pro :cheaper,

purity of the sodium hydroxide is lowwer more energy needed and its needs to be replaced regulary

membrane cell

allows what pass thru

wont allow

this ias an ion exchange membrane which divides the cells

it allows the positive sodium ions to pass through from both side but it wont allow the negative chloride ions

pro and con of membrane cell

its expensive

high purity of sodium hydroxide

less enrgy