1. Kuliah Non Fe 8 Mei 2008 Gold

6. 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 rock behind. 2. Excess Zinc metal is added to the Cyanide 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.

8. 7 MetalPrice 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 LeadPb 13,000 16,000 110,000,000 4,400 1,700,000 41,000 7,500 Iron (steel)Fe 450