Recycling of metals helps in the preservation of natural resources.
Alchemy is the medieval forerunner of chemistry, concerned with the transmutation of matter, in particular with attempts to convert base metals into gold or find a universal elixir.
Archimedes is considered by many as the greatest scientist of the ancient world. Born in Syracuse, Greece, in 287 BC, Archimedes was equally adept at Mathematics, Physics and Astronomy, besides being a prolific inventor and engineer. Among his many inventions is the Archimedes screw, the Archimedes Claw, the heat ray, the block-and-tackle pulley, the odometer, an improved version of the catapult and the basic principles for the for the lever. Many of his inventions, theories and concepts are still in use today.
A good conductor allows the electric current to pass through it freely while an insulator does not allow the electric current to pass through it. Conductors are mostly metals like copper. Insulators are mostly non-metallic solids which have extremely high resistance towards the flow of charge and do not allow the charge to flow through them.
The periodic table is an arrangement of the chemical elements, organized on the basis of their atomic numbers, electron configurations and recurring chemical properties.