Suppose that a molecule has four bonding groups and one lone pair on the central atom. Suppose further that the molecule is confined to two dimensions (this is a purely hypothetical assumption for the sake of understanding the principles behind VSEPR theory). Make a sketch of the molecule and estimate the bond angles.

Compare and contrast the molecular orbital and ionic bonding descriptions of LiF.

If you have three electron regions around a central atom, how can you have a triangular planar molecule? An angular molecule? What bond angles are predicted in each case?

Consider the following molecules: SiH4, PH3, H2S. In each case, a central atom is surrounded by four electron pairs. In which of these molecules would you expect the bond angle to be less than 109.5? Explain your reasoning.

Use valence bond theory to describe the bonding in methylamine. CH3NH2.

For each of the following molecules, complete the Lewis structure and use the VSEPR model to determine the bond angles around each central atom. Note that the drawings are only skeleton structures and may depict the angles incorrectly.

Could the anion Li2 exist? What is the ions bond order?

It is possible to write a simple Lewis structure for the SO42- ion, involving only single bonds, which follows the octet rule. However, Linus Pauling and others have suggested an alternative structure, involving double bonds, in which the sulfur atom is surrounded by six electron pairs. (a) Draw the two Lewis structures. (b) What geometries are predicted for the two structures? (c) What is the hybridization of sulfur in each case? (d) What are the formal charges of the atoms in the two structures?

Methylcyanoacrylate is the active ingredient in super glues. Its Lewis structure is (a) How many sigma bonds are in the molecule? (b) How many pi bonds are in the molecule? (c) What is the hybridization of the carbon atom bonded to nitrogen? (d) What is the hybridization of the carbon atom bonded to oxygen? (e) What is the hybridization of the double-bonded oxygen?

Lets look more closely at the process of hybridization. (a) What is the relationship between the number of hybrid orbitals produced and the number of atomic orbitals used to create them? (b) Do hybrid atomic orbitals form between different p orbitals without involving 5 orbitals? (c) What is the relationship between the energy of hybrid atomic orbitals and the atomic orbitals from which they are formed?