What does the arrangement of the periodic table tell scientists

The arrangement of the periodic table leads us to visualize certain trends among the atoms.

Elements are arranged from left to right and top to bottom in order of increasing atomic number.

The vertical columns (groups) of the periodic table are arranged so that all its elements have the same number of valence electrons (outer ring). All elements within a certain group share similar properties.

The rows are called periods. All elements in a row have the same number of electron shells.