Question

The long form of the periodic table consists of ___ horizontal rows and ___vertical columns.

• A. 6 and 17
• B. 7 and 7
• C. 5 and 7
• D. 7 and 18

Answer 1

Answer: (D)

7 and 18

The long form of periodic table (modern periodic table) has $7$ horizontal rows called periods and $18$ vertical columns called groups. Thus the answer is option D-$7,18$