A. 5
B. 6
C. 7
D. None of these.
Submitted by: Nadar Ali Buriro
The modern periodic table was created by Mosley.
There are 7 horizontal rows which are called periods. They are also called series.
Also, the modern periodic table consists of 18 vertical columns which are called groups.
Correct Answer: 7 ✔
Last Updated: August 11, 2023