the periodic table is organized into: horizontal rows called periods, vertical columns called groups. the…

the periodic table is organized into: horizontal rows called periods, vertical columns called groups. the periodic table contains ? periods and ? groups.

the periodic table is organized into: horizontal rows called periods, vertical columns called groups. the periodic table contains ? periods and ? groups.

Answer

Explanation:

Step1: Recall periodic table structure

The periodic table has 7 horizontal rows (periods).

Step2: Recall group number

The periodic table has 18 vertical columns (groups).

Answer:

7, 18