A row of elements in the periodic table is called a period. As you look at the elements in a period from the left side of the table to the right side, the properties of the elements change in the same way for every
period. A column of elements in the periodic table is called a group. Groups are also called families. The
elements in each group have properties that are the same. For example, the elements in Group 1 are
metals that react very quickly with water.