1. A Review of General Chemistry

Rank the bonds from most polar to least polar.

c. H—O, H—N, H—C

For each compound, state whether its bonding is covalent, ionic, or a mixture of covalent and ionic.

a. NaCl

b. NaOH

c. CH₃Li

d. CH₂Cl₂

e. NaOCH₃

f. HCO₂Na

g. CF₄

For the molecules shown, indicate the direction of the dipole moment.

(a)

Rank the following elements from least electronegative to most electronegative.

Na, Si, F, Mg, C, O, N

According to the potential map for the ammonium ion <IMAGE>, which atom has the greatest electron density?

(i) Using the periodic trend, choose the more electronegative atom in each pair. For one pair, you'll need to look at the actual Pauling values. (ii) For which one? (iii) Why?

(d) B vs. Si

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

(b) C vs. 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

Which bond is stronger? Briefly explain why.

b.

Given the Lewis structures, indicate the direction of the dipole moment, if there is one.

(e)

Which is more reactive, an organolithium compound or an organosodium compound? Explain your answer.

Account for the difference in the shape and color of the potential maps for ammonia and the ammonium ion in Section 1.11.

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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?

2. HNO₃

Without looking at Figure 2.20, use your intuition to estimate whether a bond is ionic, polar covalent, or covalent.

(a) Na―Cl

Which oxygen atom has the greater electron density?