Question

why electronegativity played a huge part and identifying the polarity of certain molecule or substance​

Answer 1

Answer:

Electronegativity measures a particular atom's attraction for electrons. The unequal sharing of electrons within a bond leads to the formation of an electric dipole (a separation of positive and negative electric charge). ... Bonds can fall between one of two extremes, from completely nonpolar to completely polar.

Answer 2

Explanation:

1. Electronegativity is the tendency of an atom to attract shared electrons (or electron density) to itself. An atom's electronegativity is affected by both its atomic number and the distance at which its valence electrons reside from the charged nucleus. ( most electronegative element is fluorine ).
2. electronegative atom is the one with the partial negative charge. The greater the difference in electronegativity, the more polarized the electron distribution and the larger the partial charges of the atoms
3. When non-identical atoms are covalently bonded, the electron pair will be attracted more strongly to the atom that has the higher electronegativity.
4. This results in a polar covalent bond. Polarity refers to a separation of electric charge leading to a molecule or its chemical groups having an electric dipole moment.
5. The electronegativity helps us to study the dipole moment and the distortion of the electron cloud of opposite atom.

   

I know the solution is a bit lengthy, but will help to clear the concept.

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