Question

The elements of same group of the periodic table have-
1. Same no. of protons
2. Same valence shells
3. Same valence electrons
4. Same electron affinity

Answer 1

Correct Answer - Option 3 : Same valence electrons

Explanation:

• In Modern Periodic Table elements present in the same period will have the same number of shells.
• In the Modern periodic table, elements are arranged in a series of rows. Elements of the same period have the same number of electron shells.
• As the elements in a group have the same number of electrons in the outermost shell and valency depends upon the valence electrons in an atom. Therefore all the elements of a group have the same valency or valence electron.

Difference between Period and Group
Period	Group
Horizontal rows of the periodic table of elements are the periods.	The vertical columns of the periodic chart are what we call Groups.
There are seven such periods in the table, each numbered from 1 to 7.	There are 18 groups in the periodic table.
All the elements in the period have the same number of shells. The number of electrons in this last shell increase by one across any given period	As you go down the group the valence electrons remain the same but the number of shell increase.