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). Draw the molecule and estimate the bond angles.

• explain how hybridization reconciles observed molecular shapes with the orbital overlap model.

How many central atoms does the molecule H2NCH3 have, and what is the shape about each?

An objectionable component of smog is acetyl peroxide, which has the following skeleton structure. (a) Draw the Lewis structure of this compound. (b) Write the bond angles indicated by the numbered angles.

A student who missed this class needs to know how to predict the bond angles and shape of amolecule from looking at its bond-line representation. Write a concise but complete explanationfor this student.

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

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?

Consider the following compounds: CO2, SO2, KrF2, SO3, NF3, IF3, CF4, SF4, XeF4, PF5, TF5, and SCl6. These 12 compounds are all examples of different molecular structures. Draw the Lewis structures for each and predict the molecular structures. Predict the bond angles and the polarity of each. (A polar molecule has a net dipole moment, while a nonpolar molecule does not.) See Exercises 25 and 26 for the molecular structures based on the trigonal bipyramid and the octahedral geometries.