Chapter 8

What is the difference between a covalent molecular solid and a covalent network solid? Do their physical properties differ? Explain your answer.

For each pair, indicate the more polar bond by circling the negative end of its dipole. a. \(C-S, C-O\) b. \(C-F, C-N\) c. \(P-H, P-C l\)

For each of the bonds listed, tell which atom is more negatively charged. \(\begin{array}{ll}{\text { a. } C-H} & {\text { c. } C-S} \\ {\text { b. } C-N} & {\text { d. } C-O}\end{array}\)

Predict which bond is the most polar. $$ \begin{array}{ll}{\text { a. } C-O} & {\text { c. } C-C l} \\ {\text { b. } S i-O} & {\text { d. } C-B r}\end{array} $$

Rank the bonds according to increasing polarity. $$ \begin{array}{l}{\text { a. } C-H} \\ {\text { b. } N-H} \\ {\text { c. } S i-H}\\\\{\text { d. } O-H} \\ {\text { e. } C l-H}\end{array} $$

Refrigerant The refrigerant known as freon-14 is an ozone-damaging compound with the formula \(\mathrm{CF}_{4}\) . Why is the CF_ molecule nonpolar even though it contains polar bonds?

Determine if these molecules and ion are polar. Explain your answers. $$ \begin{array}{ll}{\text { a. } \mathrm{H}_{3} \mathrm{O}^{+}} & {\text { c. } \mathrm{H}_{2} \mathrm{S}} \\ {\text { b. } \mathrm{PCl}_{5}} & {\text { d. } \mathrm{CF}_{4}}\end{array} $$

Use Lewis structures to predict the molecular polarities for sulfur difluoride, sulfur tetrafluoride, and sulfur hexafluoride.

Write the formula for each molecule. a. chlorine monoxide b. arsenic acid c. phosphorus pentachloride d. hydrosulfuric acid

Name each molecule. a. \(\mathrm{PCl}_{3}\) b. \(\mathrm{Cl}_{2} \mathrm{O}_{7}\) c. \(\mathrm{P}_{4} \mathrm{O}_{6}\) d. \(\mathrm{NO}\)

Draw the Lewis structure for each molecule or ion. a. SeF \(_{2}\) b. \(C l O_{2}-\) c. \(P O_{3}^{3-}\) d. \(\mathrm{POCl}_{3}\) e. GeF_

Determine which of the molecules are polar. Explain your answers. a. \(C-O\) b. Si- O c. Ge \(-0\) d. \(C-C l\) e. \(C-B r\)

Rocket Fuel In the 1950 s, the reaction of hydrazine with chlorine trifluoride (ClF_ s) was used as a rocket fuel. Draw the Lewis structure for \(\mathrm{ClF}_{3}\) and identify the hybrid orbitals.

Organize Design a concept map that explains how VSEPR model theory, hybridization theory, and molecular shape are related.

Compare and contrast the two covalent compounds identified by the names arsenic(III) oxide and diarsenic trioxide.

Apply The structural formula for acetonitrile, CH_ 3 CN, is shown below. Examine the structure of the acetonitrile molecule. Determine the number of carbon atoms in the molecule, identify the hybrid present in each carbon atom, and explain your reasoning.

Write the correct chemical formula for each compound. (Chapter 7\()\) a. calcium carbonate b. potassium chlorate c. silver acetate d. copper (II) sulfate e. ammonium phosphate

Write the correct chemical name for each compound. (Chapter 7\()\) a. Nal b. Fe \(\left(\mathrm{NO}_{3}\right)_{3}\) c. \(\operatorname{Sr}(\mathrm{OH})_{2}\) d. \(\mathrm{CoCl}_{2}\) e. \(\mathrm{Mg}\left(\mathrm{BrO}_{3}\right)_{2}\)

Antifreeze Research ethylene glycol, an antifreeze- coolant, to learn its chemical formula. Draw its Lewis structure and identify the sigma and pi bonds.

Determine the molecular formula for luminol and draw its Lewis structure.