Copper has been used by humans for as much as 7000 years and elements such as gold, silver, tin, lead and mercury have ... line in the diagram of the periodic table above separates the metals ...

The periodic table of chemical elements, often called the periodic table, organizes all discovered chemical elements in rows (called periods) and columns (called groups) according to increasing atomic ...

That’s why this periodic table clock really caught our eye. [gocivici]’s idea is a simple one: light up three different elements with three different colors for hours, minutes, and seconds ...