Question

Question 5
Which of the following statements about the Modern Periodic Table is correct?

(a) It has 18 horizontal rows known as Periods
(b) It has 7 vertical columns known as Periods
(c) It has 18 vertical columns known as Groups
(d) It has 7 horizontal rows known as Groups

Answer 1

Option (c) is correct.
The group number is the number assigned to the vertical columns of the modern periodic table. Elements within the same group have the same number of electrons in their outer electron shells and hence similar chemical properties. There are 18 groups in the modern periodic table