The vertical columns on the periodic table are known as

• A. Periods
• B. Groups
• C. Metalloids
• D. Ions

Answer: (B)

Vertical columns on the periodic table are called groups. Elements in the same group have the same number of valence electrons, which largely determines their chemical properties and typical reactions, so elements in a column tend to behave similarly. The horizontal rows are periods, reflecting successive electron shells being filled as you move across the table. Metalloids describe a category of elements with intermediate properties, not a column, and ions are charged particles formed by gaining or losing electrons, not the naming of a column.