Chapter 4

How does the number of valence electrons in the neutral atom of an element relate to the element's group number?

Which electrons in an atom are considered valence electrons?

Describe the differences in bonding between covalent and ionic compounds.

How is it possible for a compound to contain both covalent and ionic bonds?

Which of these substances has the most negative lattice energy? (a) \(\mathrm{KCl},\) (b) \(\mathrm{TiO}_{2},(\mathrm{c}) \mathrm{BaCl}_{2},(\mathrm{d}) \mathrm{KI}\)

Rank the following ionic compounds, which have the same crystal structure, from least negative to most negative lattice energy: \(\mathrm{CsCl}, \mathrm{CsBr},\) and \(\mathrm{CsI}.\)

Rank the following ionic compounds in order of increasing coulombic attraction between their ions: \(\mathrm{KBr}, \mathrm{SrBr}_{2},\) and \(\mathrm{CsBr}.\)

Rank the following ionic compounds in order of increasing coulombic attraction between their ions: \(\mathrm{BaO}, \mathrm{BaCl}_{2},\) and \(\mathrm{CaO}.\)

What is the role of Roman numerals in the names of the compounds formed by transition metals?

Why does the name of a binary ionic compound in which the cation is from a group 1 or group 2 element not need a Roman numeral after the element's name?

Consider a mythical element \(\mathrm{X},\) which forms two oxoanions: \(\mathrm{XO}_{2}^{2-}\) and \(\mathrm{XO}_{3}^{2-} .\) Which of the two has a name that ends in -ite?

What are the names of these compounds of nitrogen and oxygen? (a) \(\mathrm{NO}_{3} ;\) (b) \(\mathrm{N}_{2} \mathrm{O}_{5} ;\) (c) \(\mathrm{N}_{2} \mathrm{O}_{4} ;\) (d) \(\mathrm{NO}_{2} ;\) (e) \(\mathrm{N}_{2} \mathrm{O}_{3}\) (f) \(\mathrm{NO} ;(\mathrm{g}) \mathrm{N}_{2} \mathrm{O} ;\) (h) \(\mathrm{N}_{4} \mathrm{O}\)

More than a dozen neutral compounds containing only sulfur and oxygen have been identified. What are the chemical formulas of the following six? (a) sulfur monoxide; (b) sulfur dioxide; (c) sulfur trioxide; (d) disulfur monoxide; (e) hexasulfur monoxide; (f) heptasulfur dioxide

Predict the formula and give the name of the ionic compound formed by the following pairs of elements: (a) sodium and sulfur; (b) strontium and chlorine; (c) aluminum and oxygen; (d) lithium and hydrogen.

Predict the formula and give the name of the ionic compound formed by the following pairs of elements: (a) potassium and bromine; (b) calcium and hydrogen; (c) lithium and nitrogen; (d) aluminum and chlorine.

What are the names of the cobalt oxides that have the following formulas? (a) \(\operatorname{Co} \mathrm{O} ;\) (b) \(\mathrm{Co}_{2} \mathrm{O}_{3} ;\) (c) \(\mathrm{CoO}_{2}.\)

What are the formulas of the following copper minerals? a. cuprite, copper(I) oxide b. chalcocite, copper( \(I\) ) sulfide c. covellite, copper(II) sulfide

Give the formula and charge of the oxoanion in each of the following compounds: (a) sodium hypobromite; (b) potassium sulfate; (c) lithium iodate; (d) magnesium nitrite.

Give the formula and charge of the oxoanion in each of the following compounds: (a) sodium tellurite; (b) potassium arsenate; (c) barium selenate; (d) potassium bromate.

What are the names of the following ionic compounds? (a) \(\mathrm{NiCO}_{3} ;\) (b) \(\mathrm{NaCN} ;\) (c) \(\mathrm{LiHCO}_{3} ;\) (d) \(\mathrm{Ca}(\mathrm{ClO})_{2}\)

What are the names of the following ionic compounds? (a) \(\mathrm{Mg}\left(\mathrm{ClO}_{4}\right)_{2} ;\) (b) \(\mathrm{NH}_{4} \mathrm{NO}_{3} ;(\mathrm{c}) \mathrm{Cu}\left(\mathrm{CH}_{3} \mathrm{COO}\right)_{2}\) (d) \(\mathrm{K}_{2} \mathrm{SO}_{3}\)

Give the name or chemical formula of each of the following acids: (a) HF; (b) \(\mathrm{H}_{2} \mathrm{SO}_{3} ;\) (c) phosphoric acid; (d) nitrous acid.

Give the name or chemical formula of each of the following acids: (a) HBr; (b) HIO_ \(_{4} ;\) (c) selenous acid; (d) hydrocyanic acid.

Write the chemical formulas of the following compounds: (a) potassium sulfide; (b) potassium selenide; (c) rubidium sulfate; (d) rubidium nitrite; (e) magnesium sulfate.

Write the chemical formulas of the following compounds: (a) aluminum nitride; (b) ammonium sulfite; (c) rubidium chromate; (d) ammonium nitrate; (e) aluminum selenite.

What are the names of the following compounds? (a) MnS; (b) \(\mathrm{V}_{3} \mathrm{N}_{2} ;\) (c) \(\mathrm{Cr}_{2}\left(\mathrm{SO}_{4}\right)_{3} ;\) (d) \(\mathrm{Co}\left(\mathrm{NO}_{3}\right)_{2} ;\) (e) \(\mathrm{Fe}_{2} \mathrm{O}_{3}\)

What are the names of the following compounds? (a) RuS; (b) \(\mathrm{PdCl}_{2} ;\) (c) \(\mathrm{Ag}_{2} \mathrm{O} ;\) (d) \(\mathrm{WO}_{3} ;\) (e) \(\mathrm{Pt} \mathrm{O}_{2}\)

Which is the formula of sodium sulfite? (a) \(\mathrm{Na}_{2} \mathrm{S}\) (b) \(\mathrm{Na}_{2} \mathrm{SO}_{3} ;\) (c) \(\mathrm{Na}_{2} \mathrm{SO}_{4} ;\) (d) \(\mathrm{NaSH}\)

Which is the formula of barium nitrate? (a) \(\mathrm{Ba}_{3} \mathrm{N}_{2}\) (b) \(\mathrm{Ba}_{2} \mathrm{NO}_{3} ;(\mathrm{c}) \mathrm{Ba}_{2}\left(\mathrm{NO}_{3}\right)_{2} ;(\mathrm{d}) \mathrm{Ba}\left(\mathrm{NO}_{3}\right)_{2}\)

Some critics described G. N. Lewis's approach to explaining covalent bonding as an exercise in double counting and therefore invalid. Explain the basis for the criticism.

Does the octet rule mean that a diatomic molecule must have 16 valence electrons?

Why is the bonding pattern in water \(\mathrm{H}-\mathrm{O}-\mathrm{H}\) and not \(\mathrm{H}-\mathrm{H}-\mathrm{O} ?\)

Does each atom in a pair that is covalently bonded always contribute the same number of valence electrons to form the bonds between them?

Draw Lewis symbols of potassium, magnesium, and phosphorus.

Draw Lewis symbols of gallium, tellurium, and iodine.

Draw Lewis symbols for \(\mathrm{K}^{+}, \mathrm{Al}^{3+}, \mathrm{N}^{3-},\) and \(\mathrm{I}^{-}.\)

Draw Lewis symbols for the most stable ions formed by lithium, magnesium, aluminum, and fluorine.

Which of the following ions have a complete valence-shell octet? \(\mathrm{B}^{3+}, \mathrm{I}^{-}, \mathrm{Ca}^{2+},\) or \(\mathrm{Pb}^{2+}.\)

How many valence electrons are in each of the following atoms or ions? \(\mathrm{Xe}, \mathrm{Sr}^{2+}, \mathrm{Cl},\) and \(\mathrm{Cl}^{-}.\)

How many valence electrons does each of the following species contain? (a) \(\mathrm{N}_{2} ;\) (b) \(\mathrm{HCl} ;(\mathrm{c}) \mathrm{NH}_{4}^{+} ;(\mathrm{d}) \mathrm{CN}^{-}.\)

How many valence electrons does each of the following species contain? (a) \(\mathrm{H}^{+} ;\) (b) \(\mathrm{H}_{3} \mathrm{O}^{+} ;\) (c) \(\mathrm{CO}_{2} ;\) (d) \(\mathrm{CH}_{4}.\)

Draw Lewis structures for the following diatomic molecules and ions: (a) \(\mathrm{CO} ;\) (b) \(\mathrm{O}_{2} ;\) (c) \(\mathrm{ClO}^{-} ;\) (d) \(\mathrm{CN}^{-}.\)

Draw Lewis structures for the following molecules and ions: (a) \(\mathrm{Br}_{2} ;\) (b) \(\mathrm{H}_{3} \mathrm{O}^{+} ;\) (c) \(\mathrm{N}_{2} ;\) (d) \(\mathrm{HF}\)

Draw Lewis structures for the following molecular compounds and ions: (a) \(\mathrm{CCl}_{4} ;\) (b) \(\mathrm{BH}_{3} ;(\mathrm{c}) \mathrm{SiF}_{4} ;\) (d) \(\mathrm{BH}_{4}^{-}\) (e) \(\mathrm{PH}_{4}^{+}\)

Draw Lewis structures for the following molecular compounds and ions: (a) \(\mathrm{AlCl}_{3} ;\) (b) \(\mathrm{PH}_{3} ;\) (c) \(\mathrm{H}_{2} \mathrm{Se}\) (d) \(\mathrm{NO}_{2}^{-} ;\) (e) \(\mathrm{A} 1 \mathrm{H}_{4}^{-}\)

Greenhouse Gases Chlorofluorocarbons (CFCs) are compounds linked to the depletion of stratospheric ozone. They are also greenhouse gases. Draw Lewis structures for the following CFCs: a. \(\overline{\mathrm{CCl}}_{3} \mathrm{F}\) (Freon 11 ) b. \(\left.\mathrm{CCl}_{2} \mathrm{F}_{2} \text { (Freon } 12\right)\) c. \(\mathrm{CClF}_{3}\) (Freon 13 ) d. \(\mathrm{Cl}_{2} \mathrm{FC}-\mathrm{CClF}_{2}\) (Freon 113 ) e. \(\left.\mathrm{ClF}_{2} \mathrm{C}-\mathrm{CClF}_{2} \text { (Freon } 114\right)\)

The replacement of a halogen atom in a CFC molecule with a hydrogen atom makes the compound more environmentally "friendly." Draw Lewis structures for the following compounds: a. \(\mathrm{CHCl}_{2} \mathrm{F}\) (Freon 21 ) b. \(\left.\mathrm{CHF}_{2} \mathrm{Cl} \text { (Freon } 22\right)\) c. \(\left.\mathrm{CH}_{2} \text { ClF (Freon } 31\right)\) d. \(\left.F_{3} C-C H B r C l \text { (Halon } 2311\right)\) \(\mathrm{e} . \mathrm{Cl}_{2} \mathrm{FC}-\mathrm{CH}_{3}(\mathrm{HCFC} 141 \mathrm{b})\)

Draw Lewis structures for the following oxoanions: (a) \(\mathrm{ClO}_{2}^{-} ;\) (b) \(\mathrm{SO}_{3}^{2-} ;\) (c) \(\mathrm{HCO}_{3}^{-}\)

Draw Lewis structures for the following oxoanions: (a) \(\mathrm{BrO}_{4}^{-} ;\) (b) \(\mathrm{SeO}_{4}^{2-} ;\) (c) \(\mathrm{HPO}_{4}^{2-}\)

Skunks and Rotten Eggs Many sulfur-containing organic compounds have characteristically foul odors: butanethiol $\left(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{SH}\right)$ is responsible for the odor of skunks, and rotten eggs smell the way they do because they produce tiny amounts of pungent hydrogen sulfide, $\mathrm{H}_{2} \mathrm{S}\(. Draw the Lewis structures for \)\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{SH}\( and \)\mathrm{H}_{2} \mathrm{S}.$