5 Steps to a 5 AP Chemistry

take much more energy to vaporize water, thus, water has a lower vapor pressure and higher

boiling point.

Experimental

The concept of intermolecular forces is important in the separation of the components of

a mixture. Experiment 18 in the Experimental chapter utilizes this concept.

Common Mistakes to Avoid

1.Don’t confuse the various types of intermolecular forces.

2.The melting point and the freezing point are identical.

3.Hydrogen bonding can occur only when a hydrogen atom is directly bonded to an N,

O, or F atom.

4.When moving from point to point in a phase diagram, pay attention to which phase

transitions the substance exhibits.

5.In looking at crystal lattice diagrams, be sure to count all the particles, in all three dimen-

sions, that surround another particle.

 Review Questions

Answer the following questions. You have 20 minutes, and you may not use a calculator.

You may use the periodic table at the back of this book.

Solids, Liquids, and Intermolecular Forces  173

Choose from the following descriptions of solids
for questions 1–4.

(A) composed of macromolecules held together

by strong bonds

(B) composed of atoms held together by delocal-

ized electrons

(C) composed of positive and negative ions held

together by electrostatic attractions

(D) composed of molecules held together by

intermolecular dipole–dipole interactions

(E) composed of molecules held together by

intermolecular London forces

1.Fe(s)

2.KNO 3 (s)

3.SiO 2 (s)

4.HCl(s)

For questions 5 and 6 choose from the following.

(A) an ionic solid

(B) a metallic solid

(C) a molecular solid containing nonpolar molecules

(D) a covalent network solid

(E) a molecular solid containing polar molecules

5.Diamond, C(s)

6.Solid sulfur dioxide, SO 2 (s)

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