the periodic table arranges the elements in order of increasing atomic number in horizontal rows of such length those elements with similar properties recur periodically
they fall directly beneath each other in the table
the elements is a given vertical column are referred to as a family or group
the physical and chemical properties of the elements in a given family change gradually as one goes from one element in the column to the next
by observing the trend in properties the elements can be arranged in order in which they appear in the Periodic table