The circled column labeled with "1" is called a family/group . There are groups/families on the Periodic Table of Elements. Elements in the same group on the Periodic Table are similar because they have the same number of . This also means they have similar . The circled row labeled "2" is called a . There are periods on the table. Elements in the same period are similar because that have the same number of or electron shells.

Answer 1

The circled column labeled with "1" is called a family/group. There are groups/families on the Periodic Table of Elements. Elements in the same group on the Periodic Table are similar because they have the same number of valence electrons. This also means they have similar chemical properties. The circled row labeled "2" is called a period. There are periods on the table. Elements in the same period are similar because they have the same number of energy levels or electron shells.