electrolysis Flashcards
electrodes made of
graphite
electrolyte must be…
- must be conductor of electricity
- must be ionic compound (aq/molten)
electrolyte undergoes chemical reaction
components of electrolysis
- batteries
- wires
- electrodes
- electrolytes
why cannot do electrolysis on solid ionic compound
cannot conduct electricity, solid form
When NaCl (l) means…
- molten
- pure
When NaCl (aq) means…
- aqueous
- impure
neg/pos charge ions in electrolyte move to cathode/anode?
anion -> cathode
cations -> anode
what is discharge
lose charge
i.e. cation
Na+ (l) + e- -> Na (l)
molten
metal element
forms on surface of water
globules of silvery metal forms
h2o (l) electrolysis
no reaction
h2o(l) does not have ions
H+, Oh- ions only present, ionic compound (aq)
In very conc. soln (aq)
will number of Cl- > Oh-
no
- Cl- ions will nvr outnumber Oh-
- Oh- is solvent
- in conc. soln, no of Cl- ions is more than usual
which anions are not affected by conc. (anode)?
what happens instead?
- So4 2-, No3 -
- even when conc. ___ sulfate/nitrate Oh- will be selectively discharged
anyth w/ ions can be discharged i.e. acid/alkali
Oh- discharged half eqn
4OH- (aq) -> 2H2o (l) + O2 (g) + 4e-
keep in mind
OH- ions is in water when other ions present.
water (l) (pure water) // water with no ions dont have Oh-
for visible observation for electrolysis…
- any solid formed
- color change of soln.
- efferverscence + gas released
DO NOT write water level rise/drop
