Chapter 8

What is a Lewis dot symbol? What elements do we generally represent with Lewis symbols?

Without referring to Figure $8.1,$ write Lewis dot symbols for atoms of the following elements: (a) Be, (b) K, (c) Ca, (d) Ga, (e) $\mathrm{O}$ (f) $\mathrm{Br},(\mathrm{g})\mathrm{N}$ (h) I, (i) $\mathrm{As},(\mathrm{j})\mathrm{F}.$

Write Lewis dot symbols for the following ions: (a) ${\mathrm{Li}}^{+}$, (b) ${\mathrm{Cl}}^{-}$ (c) ${\mathrm{S}}^{2-}$ (d) ${\mathrm{Sr}}^{2+}$ (e) ${\mathrm{N}}^{3-}$.

Write Lewis dot symbols for the following atoms and ions: (a) $\mathrm{I},(\mathrm{b}){\mathrm{I}}^{-},(\mathrm{c})\mathrm{S},(\mathrm{d}){\mathrm{S}}^{2-},(\mathrm{e})\mathrm{P},(\mathrm{f}){\mathrm{P}}^{3-},(\mathrm{g})\mathrm{Na},(\mathrm{h}){\mathrm{Na}}^{+}$ (i) $\mathrm{Mg},(\mathrm{j}){\mathrm{Mg}}^{2+},(\mathrm{k})\mathrm{Al},(\mathrm{l}){\mathrm{As}}^{3+},(\mathrm{m})\mathrm{Pb},(\mathrm{n}){\mathrm{Pb}}^{2+}$

Explain what ionic bonding is.

Explain how ionization energy and electron affinity determine whether atoms of elements will combine to form ionic compounds.

Name five metals and five nonmetals that are very likely to form ionic compounds. Write formulas for compounds that might result from the combination of these metals and nonmetals. Name these compounds.

Explain why ions with charges greater than ±3 are seldom found in ionic compounds.

The term molar mass was introduced in Chapter $3.$ Molar mass is numerically equivalent to molecular mass, although the units are different, for a covalent compound. What is the advantage of using the term molar mass when we discuss ionic compounds?

In which of the following states would $\mathrm{NaCl}$ be electrically conducting: (a) solid, (b) molten (i.e. melted), (c) dissolved in water? Explain.