CHEMISTRY COMMUNITY

Which interaction is stronger? Dipole-dipole in the solid phase or dipole-dipole in the gas phase?

If a substance is in a gas phase, it means that the forces holding the molecules together have been overcome by the energy added. For instance, the hydrogen bonds in liquid water are broken when the water is heated, causing the water to enter a gaseous phase. So the dipole-dipole forces have the same attractive force regardless of state, but they are overpowered when the energy of the molecules in a substance passes a certain threshold.

Adding onto the previous answer, you can’t conclude that dipole-dipole interactions are stronger in the gas or solid phase. However, if you are given two samples of different polar molecules at the same temperature, if one of the samples is solid and one is gaseous, you can conclude that stronger dipole-dipole forces are likely present in the solid sample.

Dipole-dipole in the solid phase

Dipole-dipole in the gas phase is also equal to induced dipole - induced dipole, so dipole-dipole in the solid phase would have stronger IMFs.

The dipole-dipole interaction in the solid phase is stronger

With gases, they occupy more space so the attraction between the molecules are weak. Solids on the other hand are more restricted in their movement, so they have stronger dipole-dipole interactions than gases would.

Dipole-dipole in a solid phase would be stronger. The bonds in a solid are tightly held and rigid unlike those of a gas. This would mean that the attraction between the molecules in the solid phase would be greater.

Dipole-dipole in the solid phase is stronger because there are stronger attractions between molecules than in the gas phase.

Dipole-dipole in the solid phase is stronger than dipole-dipole in the gas phase because the bonds in solids are stronger, thus the attraction between molecules is greater.

I'm pretty sure that in one of the UA sessions we were told to think of dipole-dipole in the gas phase as induced dipole-induced dipole, which is a very weak IMF.

So is solid stronger or are they both the same? or does it depend on the molecule, not the state

Nathan Rothschild_3D wrote:So is solid stronger or are they both the same? or does it depend on the molecule, not the state

I think it is safe to say that the intermolecular forces in a solid compound are generally stronger than in a gas phase

Solid phase

Tiffany Vo 3G wrote:With gases, they occupy more space so the attraction between the molecules are weak. Solids on the other hand are more restricted in their movement, so they have stronger dipole-dipole interactions than gases would.

So are all intermolecular bonds between gases generally weaker than those between solids?

Dipole-dipole in the solid phase is stronger than dipole-dipole in the gas phase.