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

Use the symbols δ⁺ and δ⁻ to show the direction of the polarity of the indicated bond in each of the following compounds:

e. HO—Br

f. H₃C—Li

After examining the potential maps for LiH, HF, and H₂, answer the following questions:

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a. Which compounds are polar?

b. Why does LiH have the largest hydrogen?

c. Which compound has the hydrogen that would be most apt to attract a negatively charged molecule?

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

Which of the following compounds have a dipole moment of zero?

The C=O double bond has a dipole moment of about 2.4 D and a bond length of about 1.23 Å.

a. Calculate the amount of charge separation in this bond.

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 alkene, indicate the direction of the dipole moment. For each pair, determine which compound has the larger dipole moment

b. cis-1,2-dibromoethene or trans-2,3-dibromobut-2-ene

For each alkene, indicate the direction of the dipole moment. For each pair, determine which compound has the larger dipole moment.

c. cis-1,2-dibromo-1,2-dichloroethene or cis-1,2-dichloroethene