VSEPR Theory and Shapes

In Level 2 Chemistry, we only worry about molecules with a maximum of four regions of electron density (bonds and/or lone pairs of electrons) around the central atom.

NOTE: Error at 8:30. Tetrahedral bond angles are 109.5°, not 107°.

However, the bond angle in water is indeed around 107° due to the increased

repulsion caused by the two lone pairs of electrons.

Our task today was based around p p127-8 in Beginning Chemistry, but we used marshmallows, lollies and toothpicks to model the molecules, instead :)