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PERIODIC TABLE AND CHEMICAL BONDING INTRODUCTION

FIRST GROUP ELEMEMNTSELEMENTSATOMIC NUMBERHYDROGEN1LITHIUM3SODIUM11POTTASIUM19RUBIDIUM37CAESIUM55FRANCIUM87BOHR MODELS OF ATOMS

Elements in second periodELEMENTSATOMIC NUMBERLITHIUM3BERYLLIUM4BORON5CARBON6NITROGEN7OXYGEN8FLUORINE9BOHR MODEL OF ATOMS

Summary In group from top to bottom number of shell increasesAs number of shells increases size of the atom also increases.In period ,number period is equal to number of shells.In period from left to right size of atom decreases.From left to right the number of electrons increases in the shell.So effect of nuclear attraction increases from left to right and size of atom decreases. How the atomic size in group varies?How the atomic size in period varies?Lithium is greater than fluorine, why?Atomic number of oxygen is 6, True OR False?

ASSIGNMENTIn periodic table smaller atom is at the right most top, Examine this statement. THANKS