- #1
bijiibaa
- 1
- 0
Do lone pairs in a molecule have dipole moments? and does net dipole always go in the direction of the lone pairs?
Also and are important exceptions to the non-participation of lone pairs in dipole moments. You might think that ammonia has smaller dipole moment than nitrogen trifluoride but actually its the opposite way. Why?
GeneralChemTutor said:Saying that lone pairs contribute to the net dipole moment in that it contributes to the shape of the molecule is a bit of a stretch. There's no need to ask if a molecule has lone pairs to determine dipole moments and this was my point from the beginning.
"does this molecule have lone pairs?" or should we rather ask "what is the shape of this molecule."
The dipole moment of a MOLECULE is then the resultant vector of all the BOND dipoles. The shape of the molecule determines where all the vectors point and hence the direction of the resultant vector. The shape is a result of orbital hybridization (and VSEPR). Lone pairs contribute to the shape.
shrumeo said:The dipole moment of a BOND depends on differences in e-negativity between the 2 atoms in the BOND.
The dipole moment of a MOLECULE is then the resultant vector of all the BOND dipoles. The shape of the molecule determines where all the vectors point and hence the direction of the resultant vector. The shape is a result of orbital hybridization (and VSEPR). Lone pairs contribute to the shape.
GeneralChemTutor said:"e-negativities are used to determine BOND---dipole moments"
My point exactly, there is no other "dipole moments." There is a broader subject, it's called electron distribution both of you have the former confused with the latter term.
Lone pairs are pairs of electrons that are not involved in chemical bonding. In molecules, they can affect the overall polarity and dipole moment by creating regions of electron density. Lone pairs tend to exert a greater influence on molecular shape and polarity compared to bonding pairs.
Lone pairs can affect the distribution of electrons in a molecule, resulting in a dipole moment. This means that molecules with lone pairs may have a higher overall dipole moment compared to molecules with only bonding pairs.
In some cases, lone pairs can cancel out dipole moments in a molecule. This is because lone pairs tend to occupy more space compared to bonding pairs, and their repulsion can result in a more symmetrical distribution of charge, leading to a cancelation of dipole moments.
Lone pairs can affect the shape of a molecule by exerting repulsive forces on bonding pairs. This can result in distortions of the molecule's geometry, leading to a non-linear or bent shape. In some cases, lone pairs can also contribute to the overall polarity of the molecule.
Yes, lone pairs can affect the reactivity of a molecule. The presence of lone pairs can make a molecule more reactive by making it more polar, increasing the potential for interactions with other molecules. Additionally, lone pairs can also participate in chemical reactions, leading to new bonds and products.