1 / 12

Intermolecular Forces

Intermolecular Forces. What Holds A Liquid Or Solid Together?. In ionic compounds, all atoms are equally bonded together in the crystal What about covalent?. Two Types of Covalent Compounds. Covalent Network Crystal - all atoms covalently bonded together equally - very strong and hard

erich-woodard
Télécharger la présentation

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

  2. What Holds A Liquid Or Solid Together? • In ionic compounds, all atoms are equally bonded together in the crystal • What about covalent?

  3. Two Types of Covalent Compounds • Covalent Network Crystal - all atoms covalently bonded together equally - very strong and hard - ex: diamond, graphite

  4. Covalent Molecular Substance - individual molecules attracted to one another through intramolecular forces - not anywhere near as strong as networks - ex: water

  5. Intermolecular Forces • Force of attraction between molecules in a covalent molecular substance • Three types: Dipole – Dipole forces Hydrogen Bond London Dispersion forces

  6. Dipole- Dipole • Between polar molecules • Positive pole of one ion attracted to the negative pole of another

  7. Hydrogen Bonding • Attraction between hydrogen atom in one molecule and an unshared pair of electrons on the atom of another molecule

  8. London Dispersion or Van der Walls Force • Hold non-polar molecules together • Caused by motion of electrons

  9. Strength of Interaction • Substances held together by ionic bonds or covalent network bonds are very rigidly connected: mostly solid at room temp and melt at very high temps • Those held by dipole-dipole or hydrogen bonds are fairly strongly connected: liquid at room temp or solids that melt at low temps • Those held by london dispersion forces are weakly connected: gases at room temp; need to be very cold to become liquid

  10. Ionic Covalent Molecular Melting Point High Low Vaporize No Maybe Crystalline Yes, hard & brittle Maybe, soft Dissolve in Water Yes Mostly no Conduct electricity when liquid Yes No Conduct electricity when dissolve in water Yes No Ionic vs. Covalent

  11. Example Substance A melts at 600oC, dissolves well in water, and does not conduct electricity when solid but does when dissolved in water. Is the substance held together by ionic or covalent bonds?

More Related