Properties, Obtaining and Applications
Hugo Martínez · Year 1 ESO · Technology
Metals are chemical elements found in nature forming minerals. They have characteristic shine, conduct electricity and heat, and deform without breaking. Three quarters of periodic table are metals.
Historical periods named after them: Copper Age (6000 BC), Bronze Age (3000 BC), Iron Age (1200 BC). Each advance allowed better tools, driving civilizations.
Fundamental in daily life: buildings, vehicles, electronics, appliances, tools. Without metals modern technological advances wouldn't exist.
From open-pit or underground mines.
Crush, grind, flotation or magnetic separation to remove impurities.
High-temperature furnaces separate metal from oxygen. Chemically refined.
Treatments: painting/galvanizing for protection.
Steel: buildings, bridges (Golden Gate). Aluminum: windows, façades. Copper: pipes, wiring.
Cars: steel (body), aluminum (engine), copper (electrical). Planes: aluminum/titanium (light). Trains: steel. Ships: naval steel.
Phones/PCs: gold, silver, copper (circuits). Lithium (batteries). Cables: copper. Chips: silicon, tantalum, gallium.
Tools: hardened steel. Machines: steel, cast iron. Kitchen: stainless steel, aluminum.
Instruments: stainless steel. Prostheses: titanium (biocompatible). Orthodontics: steel, nickel-titanium.
Metals are 100% recyclable infinite times without losing properties.
Separate in yellow container.
Reduce extraction by reusing existing. Easy-disassembly design. Minimize waste.
ANA: Hugo, explain about metals?
HUGO: Sure. Chemical elements with shine, conduct electricity/heat, deform without breaking. 3/4 of periodic table.
ANA: Historical importance?
HUGO: Ages: Copper (6000 BC), Bronze (3000 BC), Iron (1200 BC). Better tools drove civilizations.
TEACHER: Properties?
HUGO: Physical (shine, conductivity, density), Chemical (oxidation, corrosion), Mechanical (malleability, ductility, hardness).
ANA: How obtained?
HUGO: Mines→crush→separate→high-temp furnaces→refine→shape (casting, forging, rolling).
TEACHER: Uses?
HUGO: Construction (steel buildings), transport (aluminum planes), technology (gold circuits, lithium batteries), medicine (titanium prostheses).
ANA: Pollute?
HUGO: Mining pollutes: destroys ecosystems, contaminates water. But 100% recyclable. Aluminum saves 95% energy recycling.
TEACHER: Circular economy?
HUGO: Reuse vs extract. Disassembly design. Urban mining (recover from old electronics). Gold/silver/copper in old phones.
ANA: Super important to use responsibly!
HUGO: Exactly. Repair, recycle, recycled products.
END
Metals fundamental from prehistory to today. Unique properties (conductivity, malleability, ductility, resistance) make them irreplaceable in construction, transport, technology, industry, medicine.
Extraction generates major impact: destroyed ecosystems, contamination, high energy consumption. Essential to recycle: 100% recyclable infinite times.
Future: circular economy and responsible use ⚙️♻️