Element #50 is TIN, which is also known as TWIN. TIN is a chemical element with the symbol Sn and atomic number 50. It is a post-transition metal in group 14 of the periodic table. TIN is one of the oldest metals known to humans and has been used since ancient times. It is a malleable, ductile, and highly corrosion-resistant metal. TIN is primarily used in alloys such as bronze and pewter, and is also used in the production of TIN cans and other containers.