Zusammenfassung der Ressource
Electrolysis
- Positively charged ions
go to the negative
electrode (cathode)
- At the negative
electrode, positively
charged ions gain
electrons (reduction)
- Negatively charged
ions go to the positive
electrode (anode)
- At the positive
electrode, negatively
charged ions lose
electrons (oxidation)
- Electrons move through
the circuit from the
anode, through the power
supply and then through
the cathode
- Electrolysis is used to
electroplate objects. This may
be for a variety of reasons
and includes copper and
silver plating.
- If there is a mixture of ions, the
products formed depend on the
reactivity of the elements involved
- Ions that are more
reactive than hydrogen
produce hydrogen gas at
the cathode (negative
electrode)
- Ions that are less reactive
than hydrogen produce the
metal of the element at the
cathode (negative
electrode)
- Aluminium is
maufactured by the
electolysis of a molten
mixture of aluminium
oxide and cryolite.
- Aluminium forms
at the negative
electrode and
oxygen at the
positive electrode.
- The positive electrode is made
of carbon, which reacts with the
oxygen to produce carbon
dioxide.
- The electrolysis of sodium chloride
solution produces hydrogen and
chlorine. Sodium hydroxide solution is
also produced.
- There are important reagents for the
chemical industry eg sodium for the
production of soap and chlorine for the
production of bleach and plastics