Wednesday, May 18, 2011

Exam Review Question #6

List the three main types of intermolecular forces and describe how each are formed Which intermolecular forces are the strongest and why?

1) Hydrogen bonds- strongest

-these bonds are polar molecules that form when a bond is made between H and F,N, or O -the large electronegativity difference in these bonds creates stronger dipoles

2) Dipole interactions- between polar molecules

-positive pole on one molecule is attracted to the negative pole of another -similar to ionic bonds but much weaker

3) London Dispersion forces- between non-polar molecules (weakest of all forces)

-step 1: Two molecules get close to each other

-step 2: The electrons in one molecule momentarily shift to form a dipole

-step 3: The momentary dipole in one molecule induces a dipole in another and they form an interaction


  1. Great job Ryan! I like the organization and the information is very accurate. The only change I could see to make is to maybe elaborate and explain a little bit about what polar means and what a dipole interaction really does when it turns polar for a second, but that is just more details. You are very right and i got the same answer as you. Fantastic job!!!

  2. Great job Ryan! Your response is very easy to understand and explained very well. I can't find anything wrong with your answer, so I will just add a little bit more information. Hydrogen bonds are the strongest of all the intermolecular forces, yet they are not as strong as covalent or ionic bonds. London Dispersion forces are the weakest of all the intermolecular forces because electrons momentarily shift to form a dipole and and can shift back at anytime.. London Dispersion forces get stronger the larger the molecule is because there are more electrons that can shift more easily to form the dipole. Electronegativity and polarity are factors that cause some of the forces to get stronger.