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CHEMISTRY.. SEPERATING TECHINQUES quiz on TUESDAY.. help

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wanabeastarstudent:
 ??? hey.. well i got a quiz on tuesday on thse things from the past year but i didnt study last year so can u help me wiv these topic n post websites plz?

*state of matter
*seperating techniques and mixtures
*atomic structure
*bonding (metallic,covalent,ironic and macromolecular)

thanks so much
and im doing extraction of iron (Fe), aluminuim and zinc do u have any websites? cuz i started skwl late so i missed out thanks :P u guys are great :)  :-*please help

The Golden Girl =D:
https://studentforums.biz/references-and-resources/ultimate-resource-guide-for-igcse/
Check this out :

https://studentforums.biz/sciences/chemistry-p3-762010/

The Golden Girl =D:
this as well :)

https://studentforums.biz/sciences/chemistry-p6-185010/

wanabeastarstudent:
thanks <3 im confused can someone explain this please??

 Extraction of metal (Aliminuim)
*low density ........ airoplane......body
*resist corrosion......>window+door frames
*reflection of heat......> food.........> container rust
*conductor or heat.....> kitchen wear
*conductor of electricity........> over head cables

please explain and can u give me any info about this topic im confused  :-[ ugh.. n i need to know about zinc and copper aswel... hm.. thanks a bunch
is al high density or low? i dont even know wat it means :-[ :-[ :-X :-X

Vin:
Alright I shall start from scratch, to avoid confusion. ;)

Extraction of Aluminium.

Aluminium ore --> Bauxite (Aluminium oxide/Alumina Al2O3)
Separation method --> Electrolysis



[If image too small - Right-click > View image]

Electrlysis is carried out in this, huge steel tank.
The walls are lined with Carbon which acts as the Cathode (-)
Huge blocks of carbon hang in the middle of the tank which act as the anode. (+)


Aluminium oxide/alumina is insoluble and it melts at 2045 *C, which is practically impossible to maintain that temperature in the tank environment. Therefore aluminium oxide is dissolved in molten Cryolite (sodium aluminium fluoride) which has a lower melting point.

Once this aluminium oxide dissolves, the aluminium ions and oxide ions are free to move. They move to the electrode of opposite charge.

At Cathode.
Aluminium ions gain electrons. (Reduction)

4Al3+  +  12e-  ----> 4Al

At anode
Oxygen ions lose electrons. (Oxidation)

6O2- ----> 3O2  + 12 e-

This oxygen bubbles off as carbon dioxide as the anode itself is made of carbon. So these blocks are eaten away and eventually should be replaced.

Overall reaction

2Al2O3 ---> 4Al + 3O2

Properties of Aluminium.
Aluminium is a bluish-silver, shiny metal.

It has low density - it is very light in weight

Good conductor of heat and electricity

Malleable (can be bent easily) and ductile (can be drawn into wires very easily)

It is strong and highly uncreative (Aluminium has the tendency to form a thin coating of Al2O3 over its surface when exposed to air, it never gets 'rust') and is very light. This is very useful for manufacturing of aircraft (light and strong) and food containers (because it is highly uncreative and does not corrode)

Reflection of heat -> It is a shiny metal.

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