1. A Review of General Chemistry

a. Draw a Lewis structure for each of the following:

b. Draw a structure for each of the species that shows approximate bond angles.

c. Which species have no dipole moment?

3. N₃⁻

Rank the following compounds from highest dipole moment to lowest dipole moment:

1. From what you remember of electronegativities, show the direction of the dipole moments of the following bonds.

2. In each case, predict whether the dipole moment is relatively large (electronegativity difference >0.5) or small.

a. C—Cl

b. C—H

c. C—Li

d. C—N

e. C—O

For each of the following compounds,

1. draw the Lewis structure.

2. show how the bond dipole moments (and those of any nonbonding pairs of electrons) contribute to the molecular dipole moment.

3. estimate whether the compound will have a large, small, or zero dipole moment.

e.

In each pair of atoms, which has the larger atomic radius? Which is more electronegative?

(c) O vs. S

Which molecule/s contain/snet dipoles?

Which molecule/s contain/snet dipoles?

1. CH₃N₂⁺
2. HNO₃
3. N₃^-
4. CH₃CONH₂
5. O₃

b. Draw a structure for each of the species that shows approximate bond angles.

c. Which species have no dipole moment?

Using only your intuition, rank the following covalent bonds in terms of their polarity (1 = most polar; 6 = least polar). [You can use the periodic trend of electronegativity, but don't use actual numbers.]

(a) C―C

(b) C―O

(c) C―H

(d) C―F

(e) C―Cl

(f) C―S

1. Draw the Lewis structure.

2. Show how the bond dipole moments (and those of any nonbonding pairs of electrons) contribute to the molecular dipole moment.

3. Estimate whether the compound will have a large, small, or zero dipole moment.

g. HCN

h. CH₃CHO

i. H₂C=NH

In what direction is the dipole moment in calicene? Explain.

If the dipole moment of CH₃F is 1.847 D and the dipole moment of CD₃F is 1.858 D, which is more electronegative: hydrogen or deuterium?

Refer to the electrostatic potential maps <IMAGE> to answer the following questions:

c. Why is the center of the electrostatic potential map of benzene more red than the center of the electrostatic potential map of pyridine?

Based on your answer to Assessment 2.22, would you expect a larger atom to be more or less electronegative than a smaller atom?