This video lecture from Periodic Classification of Elements and Periodicity (F.Sc. second year Chemistry) covers: Concept of nuclear interactions and bonding. Electronegativity and electro positivity and the ease of removing electrons from atoms. The screening/shielding affect and the affect of atomic size on Ionization energy and electron affinity and their trends group-wise and period-wise. Find more e-learning material and educational video lectures in Urdu at maktab.pk. These videos are free to use for promotional and commercial purpose by keeping the credits to Maktab.