Question

Number of vertical columns in the modern periodic table are:
(A)7
(B) 8
(C) 10
(D)18

Answer 1

Hint: The modern periodic table is the long form of periodic table. Vertical columns contain the groups of the modern periodic table. Elements are arranged from top to bottom in the groups.

Complete answer:
-The modern periodic table contains 7 periods and 18 groups.
-Periods are the horizontal rows from left to right.
-Groups are the vertical columns from top to bottom.
-There are 7 periods in the periodic table so OPTION (A) is incorrect.
-Although the no. of valence electrons is 8 in the last group but it belongs to group 18. So OPTION (B) is incorrect.
-The no. of groups is determined on the basis of valence shell configuration.
The number of vertical columns in the modern periodic table is 18.
So OPTION (D) is the answer.
Additional Information:
-Elements in the periods show different properties.
-Elements in the group show similar properties
-The electronic configuration is different in the period.
-The electronic configuration is the same along the group.
-Properties of the elements are a function of their atomic number. This the modern periodic law.

Note: You must read the question thoroughly because Mendeleev’s periodic table is also important and it contains 8 groups. Mendeleev’s periodic table consists of 7 periods and 8 groups. The groups in the Mendeleev’s table are divided into subgroups A and B.