What are the rows and columns on the periodic table called? How are elements in the rows similar, and how are elements in the columns similar?

In the periodic table, the rows and columns have specific names and characteristics:

Rows on the Periodic Table

• Called: Periods
• Similarity of Elements in Rows: Elements in the same period have the same number of atomic orbitals. As you move from left to right across a period, the atomic number increases, and elements gain more protons and electrons, filling the orbitals progressively.

Columns on the Periodic Table

• Called: Groups or Families
• Similarity of Elements in Columns: Elements in the same group have the same number of electrons in their outermost shell, which gives them similar chemical properties. This is why elements in a group often behave similarly in chemical reactions.

These structural features of the periodic table help in predicting the chemical behavior of elements.