Partial Charges

[Shrita Pendekanti 4B]

Can someone please clarify how we know when atoms in a molecule should have partial charges? Thanks!

[Chem_Mod]

You should look at their electronegativity and think how electron favors one over the other.

[Shrita Pendekanti 4B]

Ok, so if they are close in electronegativity, then the electrons will be more shared, giving the atoms partial rather than complete charges?

[Cat Larcheveque 2E]

Not quite? The atoms in a molecule are bonded together and share electrons. However, sometimes one atom has a higher electronegativity, and thus, pulls the electrons closer to itself. Because the electron is closer to it, that atom has a partial negative charge. On the other hand, the atom whose electron is being pulled away partially loses the negative charge of the electron. This atom now has a partial positive charge.

[Shrita Pendekanti 4B]

Oh ok, so then a greater difference in electronegativity would cause partial charges?