The Most Metallic and Most Non-metallic Element in the Periodic Table

Francium (man-made) and Cesium are the most metallic elements in the periodic table (natural).

Fluorine is the most non-metallic element in the periodic table.

While travelling from left to right in the periodic table, the non-metallic nature increases. The non-metallic property reduces as we travel down the group due to an increase in atomic size.