How Is The Periodic Table Arranged?

In order of increasing atomic number.

In a periodic table each element is generally listed with its element symbol and atomic number. Some periodic tables even structure in the elements atomic mass and other such factors like electron configuration, electro-negativity and most common valence numbers. The periodic table today comprises of 117 chemical elements. Of which, ninety are found from the earth itself and the rest come under the synthetic elements.

Elements 43 (technetium) and 61 (promethium), even though of lower atomic number than the naturally occurring element 92, uranium, are artificial; elements 93 (neptunium) and 94 (plutonium) are planned with the synthetic elements, but have been discovered in trace amounts on earth.