Q4 of 30 Page 1

Define electro positivity.

OR


The atomic radil of first group elements are given below:



State the reason behind the observed trend in the above elements.


Electro positivity is the measure of the ability of elements (mainly metals) to donate electrons to form positive ions. Example Li+, Na+, K+.

OR


As we moved own in a group, addition of new shells occurs which increases the distance between nucleus and valence electrons there by decreasing the pull effect of nucleus on the valence electrons, resulting in the increase in atomic radius of the atom.


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