Chapter 8

Write the abbreviated electron configuration of the \(\mathrm{Co}^{3+}\) ion. How many unpaired electrons does the ion contain?

Write Lewis symbols for the following atoms: (a) \(\mathrm{Si}\) (b) Sb, (c) \(\mathrm{Ba}\) (d) Al, (e) \(S\).

Write Lewis symbols for the following atoms: (a) \(\mathrm{K}\) (b) Ge, (c) As, (d) \(\mathrm{Br}\) (e) Se.

Use Lewis symbols to diagram the reactions between (a) \(\mathrm{Mg}\) and \(\mathrm{S}\), (b) \(\mathrm{Mg}\) and \(\mathrm{Cl}\), and (c) \(\mathrm{Mg}\) and \(\mathrm{N}\).

Use Lewis symbols to diagram the reactions between (a) \(\mathrm{Ca}\) and \(\mathrm{Br}\), (b) \(\mathrm{Al}\) and \(\mathrm{O},\) and (c) \(\mathrm{K}\) and \(\mathrm{S}\).

Use Lewis structures to diagram the formation of (a) \(\mathrm{Br}_{2}\), (b) \(\mathrm{H}_{2} \mathrm{O},\) and \((\mathrm{c}) \mathrm{NH}_{3}\) from neutral atoms.

Use Lewis structures to diagram the formation of (a) \(\mathrm{CH}_{4}\), (b) \(\mathrm{PH}_{3}\) (c) \(\mathrm{F}_{2}\) from neutral atoms

Chlorine tends to form only one covalent bond because it needs just one electron to complete its octet. What are the Lewis structures for the simplest compound formed by chlorine with (a) nitrogen, (b) carbon, (c) sulfur, and (d) bromine?

Use the octet rule to predict the formula of the simplest compound formed from hydrogen and (a) selenium, (b) arsenic, and (c) silicon.

What would be the formula for the simplest compound formed from (a) phosphorus and chlorine, (b) carbon and fluorine, and (c) iodine and chlorine?

What would be the formula for the simplest compound formed from (a) arsenic and bromine, (b) silicon and chlorine, \((\mathrm{c})\) bromine and fluoride?

The molecule bromine monofluoride has a dipole moment of \(1.42 \mathrm{D}\) and a bond length of \(176 \mathrm{pm}\). Calculate the charge on the ends of the molecule, expressed in electronic charge units \(\left(e^{-}=1.60 \times 10^{-19} \mathrm{C}\right)\). Which atom carries the positive charge?

The dipole moment of HF is \(1.83 \mathrm{D}\) and the bond length is \(91.7 \mathrm{pm} .\) Calculate the amount of charge (in electronic charge units) on the hydrogen and the fluorine atoms in the HF molecule.

Draw Lewis structures for (a) \(\mathrm{SiCl}_{4},\) (b) \(\mathrm{PF}_{3},\) (c) ClF \(_{5}\), and (d) \(\mathrm{SCl}_{2}\).

Draw Lewis structures for (a) \(\mathrm{HIO}_{3}\), (b) \(\mathrm{H}_{2} \mathrm{CO}_{3}\), (c) \(\mathrm{TeF}_{6},\) and (d) \(\mathrm{PH}_{3}\).

Draw Lewis structures for (a) \(\mathrm{AsCl}_{4}^{+}\), (b) \(\mathrm{ClO}_{2}^{-}\), (c) \(\mathrm{HNO}_{2},\) and (d) \(\mathrm{XeF}_{2}\).

Draw Lewis structures for (a) \(\mathrm{HCO}_{3}^{-},\) (b) \(\mathrm{PCl}_{4}^{+}\), (c) \(\mathrm{PF}_{6}^{-},\) and (d) \(\mathrm{XeF}_{4}\).

Draw Lewis structures for (a) carbon disulfide, (b) the cyanide ion, (c) germanium tetrachloride, and (d) the phosphate ion.

Draw Lewis structures for (a) selenium trioxide, (b) the carbonate ion, (c) hydrogen carbonate ion, and (d) selenium dioxide.

Draw Lewis structures for (a) \(\mathrm{NO}^{+},\) (b) \(\mathrm{HClO}_{2}\), (c) \(\mathrm{H}_{2} \mathrm{SeO}_{3}\), and (d) \(\mathrm{H}_{3} \mathrm{AsO}_{4}\).

Draw the Lewis structure for (a) \(\mathrm{CH}_{2} \mathrm{O}\) (the central atom is carbon, which is attached to two hydrogens and an oxygen), and (b) \(\mathrm{SeO}_{2} \mathrm{~F}_{2}\) (the central atom is selenium, which is attached to two oxygens and two fluorines).

Draw Lewis structures for (a) the peroxide ion, \(\mathrm{O}_{2}{\underline{\phantom{xx}}}^{2-}\), and (b) \(\mathrm{POCl}_{3}\) (the central atom is phosphorus, which is attached to the oxygen and the three chlorines).

Draw the Lewis structure for \(\mathrm{HClO}_{4}\). Assign formal charges to each atom in the formula. Determine the preferred Lewis structure for this compound.

Draw the Lewis structure for \(\mathrm{SOCl}_{2}\) (sulfur bonded to two \(\mathrm{Cl}\) and one \(\mathrm{O}\) ). Assign formal charges to each atom. Determine the preferred Lewis structure for this molecule.

Use Lewis structures to show that the hydronium ion, \(\mathrm{H}_{3} \mathrm{O}^{+},\) can be considered to be formed by the creation of a coordinate covalent bond between \(\mathrm{H}_{2} \mathrm{O}\) and \(\mathrm{H}^{+} .\)

Draw the resonance structures for \(\mathrm{CO}_{3}^{2-}\). Calculate the average \(\mathrm{C}-\mathrm{O}\) bond order.

How should the \(\mathrm{N}-\mathrm{O}\) bond lengths compare in the \(\mathrm{NO}_{3}^{-}\) and \(\mathrm{NO}_{2}^{-}\) ions?

Arrange the following in order of increasing \(\mathrm{C}-\mathrm{O}\) bond length: \(\mathrm{CO}, \mathrm{CO}_{3}^{2-}, \mathrm{CO}_{2}, \mathrm{HCO}_{2}^{-}(\) formate ion \()\).

Use formal charges to establish the preferred Lewis structures for the \(\mathrm{ClO}_{3}^{-}\) and \(\mathrm{ClO}_{4}^{-}\) ions. Draw resonance structures for both ions and determine the average \(\mathrm{Cl}-\mathrm{O}\) bond order in each. Which of these ions would be expected to have the shorter \(\mathrm{Cl}-\mathrm{O}\) bond length?

In many ways, tin(IV) chloride behaves more like a covalent molecular species than like a typical ionic chloride. Draw the Lewis structure for the tin(IV) chloride molecule.

In each pair, choose the one with the more polar bonds. (Use the periodic table to answer the question.) (a) \(\mathrm{PCl}_{3}\) or \(\mathrm{AsCl}_{3}\) (b) \(\mathrm{SF}_{2}\) or \(\mathrm{GeF}_{4}\) (c) \(\mathrm{SiCl}_{4}\) or \(\mathrm{SCl}_{2}\) (d) \(\mathrm{SrO}\) or \(\mathrm{Sn} \mathrm{O}\)

How many electrons are in the outer shell of the \(\mathrm{Zn}^{2+}\) ion?

How should the sulfur-oxygen bond lengths compare for the species \(\mathrm{SO}_{3}, \mathrm{SO}_{2}, \mathrm{SO}_{3}^{2-},\) and \(\mathrm{SO}_{4}^{2-} ?\)

Explain why ions of the representative elements rarely have charges greater than +3 or smaller than -3 .

What wavelength of light, if absorbed by a hydrogen molecule, could cause the molecule to split into the ions \(\mathrm{H}^{+}\) and \(\mathrm{H}^{-}\) ? (The data required are available in this and previous chapters.)

One way of estimating the electronegativity of an atom is to use an average of its ionization energy and electron affinity. Why would these two quantities, taken together, be related to electronegativity?

The attractions between molecules of a substance can be associated with the size of the molecule's dipole moment. Explain why this is so.