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 ...

For comparison, the radius of a typical bacterium is 1 × 10-6 m and the radius of a human hair is about 1 × 10-4 m.

The covalent radius (a measure of how large individual atoms are) shows different trends if you are moving across a period or down a group. A comparison of the relative covalent radii of atoms is ...

Aluminum is a metal in group IIIA of the periodic table with atomic number 13, an atomic weight of 26.982, and a density of 2.70. It has a melting temperature of 660 C. The electronic configuration of ...

Zirconium is a metal in group IVB of the periodic table with atomic number 40, an atomic weight of 91.22, and a density of 6.49 Mg/m 3. Its melting point is 1852 C, and it boils at 3580 C. The ...