Ragita Academy

                                   Periodic table ELEMENTS- Elements are pure from of matter that are made up of one type of atom. ·        DOBEREINER- Grouped all elements in three (triads). ·        NEWLAND- Observed that when elements are arranging in increasing order of their atomic mass. Every eighteen element beginning from any element resemble the first element in its physical and chemical properties. ·        DMITRI MENDLEVE- He is a Russian chemist gave the first periodic table of elements based on his law which states that “The properties of elements are the periodic functions of their atomic mass.”   ·        Modern periodic table was given by HENERY MOSELEY. Periodic table- A tabular form of elements in group and periods highlighting the regular trends in properties of elements is called periodic table. ·        NEIL BOHR- He has given the long form of modern periodic table. Ø About groups of periodic table- 1.    Group 1. These elements are known