Atomic structure ... periodic table. In the modern periodic table, elements are in order of atomic number in periods and groups. Electronic structures model how electrons are arranged in atoms.

It is wise to plan your answer first by making some notes. This will help you to include all the key points. Six-mark ... Two elements in group 1 of the periodic table are lithium and sodium.

This year we celebrate the 150 th anniversary of Mendeleev’s achievement in formulating the structure of the periodic table that we use today. He announced his structure in 1869, but the challenge of ...

Meyer was just four years older than Mendeleev, and produced several Periodic Tables between 1864-1870. His first table contained just 28 elements, organised by their valency (how many other atoms ...