1. Extraction of metals Only some unreactive metals such as silver, gold and platinum can occur freely in nature. Most metals react with other elements to form ores.
17. Types of Steel Little carbon, with chromium & nickel Stainless steel – alloy 0.45% - 1.50% High carbon steel Up to 0.25% Mild carbon steel Percentage of carbon Steel
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19. Uses of Steel Pipes & tanks in chemical plants, making cutlery, surgical instruments Stainless steel – does not rust Make knives, hammer, cutting tools High carbon steel – strong but brittle Make steel parts in car bodies , machineries Mild carbon steel – strong, hard & malleable Uses Steel
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30. Uses of Aluminium Low density, light High tensile strength Resistant to corrosion Aircraft body Non-toxic Resistant to corrosion Good conductor of heat Food containers Low density, light Resistant to corrosion (protected by aluminium oxide) Good electrical conductivity Overhead electric cables Properties Uses
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