The Periodic Table is a well-organized chart that contains all 118 known elements in the universe. These elements are the ...

The periodic table of chemical elements, often called the periodic table, organizes all discovered chemical elements in rows ... ionization energy, and atomic radius. Many scientists worked on the ...

The periodic table The periodic table is a chart of all the elements arranged in increasing atomic number. Group 1 alkali metals The Group 1 elements, also known as the alkali metals, all react ...

However, the modern periodic table arranges the elements by increasing atomic number, rather than atomic mass. Mendeleev recognised that not all elements had been discovered yet. He left gaps in ...