kuliah non fe 8 mei 2008 gold. 6 gold metal is also extracted from the rocks of the earth. large...
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Kuliah Non Fe 8 Mei 2008
Gold
6
Gold metal is also extracted from the rocks of the Earth.Large quantities of gold bearing rock are mined from deep mines.Again, the rocks are crushed to make extraction possible.
1.Cyanide solution is added to crushed gold bearing ore to dissolve the gold and leave the unwanted rockbehind.
2. Excess Zinc metal is added to theCyanide and gold solution. The gold precipitates out and sinks to the bottom of the liquid.The zinc/cyanide solution is left behind.
4. 3.Excess zinc metal is dissolved into the solution by adding sulphuric acid.Only the gold metal is now left behind as a solid.
The heavy gold metal is filtered from the liquid.It is dried, then melted. The molten gold is poured into moulds to cool into rough gold plates for electrolytic refining.
DRAW a diagram to show the different types of atoms and molecules that are present at each stage of the process of extraction of gold from its ore.
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Metal Price in Rand/tonne
Gold
Silver
Copper
Tin
Zinc
Chemical symbol
Cu
Au
Ag
Sn
Zn
DISCUSS possible reasons for why different metals cost different prices.
Aluminium Al
Lead Pb
13,000
16,000
110,000,000
4,400
1,700,000
41,000
7,500
Iron (steel) Fe 450
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