Weak Attractions**
• Used in Lesson 2.3.
• This animation from the Molecular  Workbench represents   atoms and small molecules that are attracted to each other   (positives attract to negatives and neutral particles). These   weak attractions are electrical forces, which sometimes   cause atoms and molecules to temporarily stick together.
  + Play Animation*

Docking: Weak Attractions Add Up**
• Used in Lesson 2.3.
• Which takes more force to get un-stuck from the green   molecule: Molecule 1 or 2?

  Watch these Molecular Workbench animations to see if you   can explain why in terms of the shapes of the molecules, the

number of attractions are formed.

  + Play Animation* Molecule 1

  + Play Animation* Molecule 2

Melting a Nanoparticle
• Used in Lesson 2.3
• View an animation of a gold nanoparticle as the temperature   increases from 300 Kelvin (K) to 1000 Kelvin (K)”
  + Play Movie (QT: 1:05 min., 2 MB)