Iron. Person who discovered the element : unknown When it was discovered : before ancient times . Structure and Location. 26. 26. 26. 30. 4. 8. Iron. The electron arrangement/configuration in the atom: [ Ar ] 3d 6 4s 2 The density of the element: 7.87 g/cm3
Person who discovered the element: unknown
When it was discovered: before ancient times
Os - Osmium
Ru - Ruthenium
Hs - Hassium
Some of the first elements discovered were, gold, silver, copper, and iron. They were discovered before 1 A.D. The first periodic table was published in 1869. The creator of the periodic table was Dmitri Mendeleev. Mendeleev had left some black spaces in the periodic table because he knew that there were other elements but he hadn’t discovered them.