1 / 9

Intermolecular Forces

Intermolecular Forces. aka…. Van der Waals Forces. IM/ VdW forces are the forces of attraction between molecules – not within the molecule. VdW forces vary in strength depending on the interactions between molecules. Intermolecular Forces. Weaker force…. Dipole-Dipole.

wyome
Download Presentation

Intermolecular Forces

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Intermolecular Forces aka… Vander Waals Forces IM/VdW forces are the forces of attraction between molecules – not within the molecule. VdW forces vary in strength depending on the interactions between molecules.

  2. Intermolecular Forces Weaker force… Dipole-Dipole Polar molecules act as tiny “dipoles” (equal & opposite charges separated by short distances) Dipole – dipole forces attract between molecules such as between two water molecules. Positive H region is attracted to negative O region of a different molecule.

  3. d- attracted to (like a magnet) Electrons of one atom are attracted to another atom’s nucleus d+

  4. Cl Al O N Cl H H H Cl H H Cl S Cl Cl C H H O C O Cl Which of the following are polar molecules? Where are their dipole regions?

  5. Intermolecular Forces Stronger force… Hydrogen bonding In hydrogen bonding, a hydrogen atom is attracted to an unshared pair of electrons of an –OH, -NH, or –FH group.

  6. Hydrogen bonding Evidence… Surface Tension Enhancement of the intermolecular attractive forces at the surface

  7. What causes surface tension? The cohesive forces between molecules are shared with all neighboring atoms. Since the surface has no neighboring atoms above, they exhibit stronger attractive forces for their neighbors next to and below them

  8. Surface tension is a result of cohesive intermolecular forces

  9. How is surface tension affected by soap? Soap breaks the surface tension!

More Related