Aluminum has not always been the light, cheap metal it is now. Chemists once painstakingly toiled to produce even small amounts, largely because it quickly burned when heated to high temperatures. The Washington Monument was topped with aluminum at the end of its construction in 1884. The 6.1-pound (2.8 kg) pyramid was one of the biggest pieces created.
In 1886, aluminum alchemists Charles Martin Hall and Paul Heroult discovered, independently, a process for cheap aluminum production. The twenty-two- year-olds, from the United States and France respectively, found that molten cryolite was the optimal environment for a chemical reaction to create large amounts of aluminum.
Before being put through the Hall-Heroult process, bauxite ore must first be changed into aluminum-oxide. In the process, powdered aluminum oxide is dissolved in molten cryolite, a substance made up of sodium, aluminum, and fluoride. In the cryolite, aluminum oxide separates into highly reactive ions (charged atoms). The oxygen ions contain too many electrons, giving them a negative charge that pulls them toward positively charged carbon rods. The oxygen ions combine with the positively charged carbon to form carbon dioxide. Simultaneously, the aluminum ions are drawn toward negatively charged carbon lining the reaction container. When the aluminum contacts the carbon, it steals the carbon's excess electrons and thus becomes stable aluminum.
Aluminum is used to make food packaging and kitchen utensils, as well as having many specialized uses as a sturdy, lightweight material.
