Q15 of 60 Page 1

What is meant by 'group' in the modern periodic table? How do the following change on moving from top to bottom in a group?

(i) Number of valence electrons


(ii) Number of occupied shells


(iii) Size of atoms


(iv) Metallic character of elements


(v) Effective nuclear change experienced by valence electrons

Groups are the vertical columns in the modern periodic table.

(i) Elements having same group no. have same no. of valence electrons.


(ii) When we move down in a group, the occupied shells increase.


(iii) Due to introduction of a new shell of electrons, the size of atom increases as we move down in a group.


(iv) The metallic character of elements increases as we move down in a group.


(v) Due to introduction of a new shell of electrons, the size of atom increases, due to which the force of attraction decreases between the nucleus and electrons, As a result nuclear charge decrease.


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