Using Resources- Haber Process etc. Flashcards
When is Hydrogen formed at the cathode
Hydrogen will be produced at the cathode if the metal is more reactive than hydrogen
When will a halogen form at the anode
If the aqueous solution contains halide ions, then the halogen will be produced at the anode
How to stop rusting
Paint
Oil/Grease
Electroplating/Adding a more reactive metal than iron
Electrolysis of water
4OH- -> O2 +2H2O +4e-
2H+ +2e- ->H2
LDPE
Addition polymerisation of ethene under high pressure and in the presence of a small amount of oxygen. The polymer chains cannot pack together, so causing the low density of the polymer
HDPE
Addition polymerisation of ethene using a catalyst at 50 C. The polymer chains are straight and can pack tightly together, so causing the high density of the polymer
Thermosoftening
do not have links between different chains, and soften when heated
Thermosetting
strong links between different chains, and do not melt when heated
Soda-lime glass
Sand, sodium carbonate, limestone- transparent, brittle- used in everyday glass objects
Borosilicate glass
heat sand and boron trioxide- higher melting point than soda-lime glass, used in oven glassware, lab glassware
Clay ceramics (pottery+bricks)
shape wet clay then heat in a furnace- hard, brittle, easy to shape before manufacture, resistant to corrosion- used in crockery, construction, plumbing fixtures
What are composites
matrix (main material) with fragments of reinforcement (other materials), which allows the material’s properties to be more useful
Haber Process- temp
The forward reaction is
exothermic. Therefore,
lowering the temperature
would increase the yield of
ammonia, but would also
decrease the rate of reaction.
Haber process- pressure
There are fewer gas molecules on
the product side, so increasing the
pressure would increase the yield
and the rate of reaction. However,
it is very expensive to increase
the pressure.
Haber process- catalyst
Iron is an effective catalyst for
the Haber process. It does not
increase the yield, but does
increase the rate.
