The horizontal rows on the periodic table are called periods.

The horizontal rows on the periodic table are called periods.

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

Answer: (A)

In the periodic table, horizontal rows are called periods. This naming reflects how elements in a row share the same principal energy level for their valence electrons, and as you move from left to right within a row, properties change in a repeating pattern tied to that energy level. The statement is correct because periods are the horizontal lines. Groups, by contrast, are vertical columns, and ions are charged particles, while metalloids describe a type of element with intermediate properties.

In the periodic table, horizontal rows are called periods. This naming reflects how elements in a row share the same principal energy level for their valence electrons, and as you move from left to right within a row, properties change in a repeating pattern tied to that energy level. The statement is correct because periods are the horizontal lines. Groups, by contrast, are vertical columns, and ions are charged particles, while metalloids describe a type of element with intermediate properties.