Question

1. What are the rows of the periodic table called and what do they tell us?

Answer 1

The elements are arranged in seven horizontal rows, called periods or series, and 18 vertical columns, called groups.

Each row represents one period; the period number of an element indicates how many of its energy levels house electrons. Sodium, for instance, sits in the third period, which means a sodium atom typically has electrons in the first three energy levels.

Step-by-step explanation: