Page 11 - E-Science Prep.2 2024-2025 t1 Unit1_Neat
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Atomic                                     Atomic
   Size                                       Size

                          Atomic                           Atomic number

The atomic size is inversely                     The atomic size is directly
proportional to the atomic                 pprrooppoorrTttihoioennaaaltotliomntotighactresohgiauzreteopoauimstpodicimrneuiccmtlnybuemr inbear

    number in a period.

2-Electronegativity

Electronegativity The ability of the atom in covalent molecule to
attract the electrons of the bond towards itself.

Polar compounds-They are covalent compounds in which the difference

in electronegativity between elements forming their molecules is
relatively high

       Water molecule                   Ammonia molecule

The ability of an oxygen atom to    The ability of a nitrogen atom to attract
attract the two electrons of        the two electrons of the covalent bond
covalent bond towards is greater
than the ability of hydrogen atom.    towards it, is greater than that of a
                                                      hydrogen

2nd Prep. First Term                14 11
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