Chapter 9

Complete the following chemical equations. $$\begin{array}{l}{\text { a. } \mathrm{Na}(\mathrm{s})+\mathrm{H}_{2} \mathrm{O}(1) \rightarrow} \\ {\text { b. } \mathrm{K}(\mathrm{s})+\mathrm{H}_{2} \mathrm{O}(1) \rightarrow}\end{array}$$

Complete the following chemical equation. $$\mathrm{CuCl}_{2}(\mathrm{s})+\mathrm{Na}_{2} \mathrm{SO}_{4}(\mathrm{aq}) \rightarrow$$

Write complete ionic and net ionic equations for each of the following reactions. $$\begin{array}{l}{\text { a. } \mathrm{K}_{2} \mathrm{S}(\mathrm{aq})+\mathrm{CoCl}_{2}(\mathrm{aq}) \rightarrow 2 \mathrm{KCl}(\mathrm{aq})+\mathrm{CoS}(\mathrm{s})} \\ {\text { b. } \mathrm{H}_{2} \mathrm{SO}_{4}(\mathrm{aq})+\mathrm{CaCO}_{3}(\mathrm{s}) \rightarrow} \mathrm{H}_{2} \mathrm{O}(1)+\mathrm{CO}_{2}(\mathrm{g})+\mathrm{CaSO}_{4}(\mathrm{s})\\\ {\text { c. } 2 \mathrm{HClO}(\mathrm{aq})+\mathrm{Ca}(\mathrm{OH})_{2}(\mathrm{aq}) \rightarrow} \\ {2 \mathrm{H}_{2} \mathrm{O}(1)+\mathrm{Ca}(\mathrm{ClO})_{2}(\mathrm{aq})}\end{array}$$

A reaction occurs when hydrosulfuric acid \(\left(\mathrm{H}_{2} \mathrm{S}\right)\) is mixed with an aqueous solution of iron(III) bromide. The reaction produces solid iron(III) sulfide and aqueous hydrogen bromide. Write the chemical and net ionic equations for the reaction.

Write complete ionic and net ionic equations for each of the following reactions. $$\begin{array}{l}{\text { a. } \mathrm{H}_{3} \mathrm{PO}_{4}(\mathrm{aq})+3 \mathrm{RbOH}(\mathrm{aq}) \rightarrow 3 \mathrm{H}_{2} \mathrm{O}(1)+\mathrm{Rb}_{3} \mathrm{PO}_{4}(\mathrm{aq})} \\ {\text { b. } \mathrm{HCl}(\mathrm{aq})+\mathrm{NH}_{4} \mathrm{OH}(\mathrm{aq}) \rightarrow \mathrm{H}_{2} \mathrm{O}(\mathrm{l})+\mathrm{NH}_{4} \mathrm{Cl}(\mathrm{aq})} \\ {\text { c. } 2 \mathrm{HI}+\left(\mathrm{NH}_{4}\right)_{2} \mathrm{S}(\mathrm{aq}) \rightarrow \mathrm{H}_{2} \mathrm{S}(\mathrm{g})+2 \mathrm{NH}_{4} \mathrm{I}(\mathrm{aq})} \\ {\text { d. } \mathrm{HNO}_{3}(\mathrm{aq})+\mathrm{KCN}(\mathrm{aq})+\mathrm{HCN}(\mathrm{g})+\mathrm{KNO}_{3}(\mathrm{aq})}\end{array}$$

Paper A reaction occurs when sulfurous acid \(\left(\mathrm{H}_{2} \mathrm{SO}_{3}\right)\) is mixed with an aqueous solution of sodium hydroxide. The reaction produces aqueous sodium sulfite, a chemical used in manufacturing paper. Write the chemical and net ionic equations for the reaction.

Photosynthesis Identify the products in the following reaction that occurs in plants: Carbon dioxide and water react to produce glucose and oxygen.

Write the word equation for each of these skeleton equations. \(C_{6} \mathrm{H}_{6}\) is the formula for benzene. $$\begin{array}{l}{\text { a. } C_{6} \mathrm{H}_{6}(1)+\mathrm{O}_{2}(\mathrm{g}) \rightarrow \mathrm{CO}_{2}(\mathrm{g})+\mathrm{H}_{2} \mathrm{O}(1)} \\ {\text { b. } \mathrm{CO}(\mathrm{g})+\mathrm{O}_{2}(\mathrm{g}) \rightarrow \mathrm{CO}_{2}(\mathrm{g})} \\ {\text { c. } \mathrm{Cl}_{2}(\mathrm{g})+\mathrm{NaBr}(\mathrm{s}) \rightarrow \mathrm{NaCl}(\mathrm{s})+\mathrm{Br}_{2}(\mathrm{g})} \\ {\text { d. } \mathrm{CaCO}_{3}(\mathrm{s}) \rightarrow \mathrm{CaO}(\mathrm{s})+\mathrm{CO}_{2}(\mathrm{g})}\end{array}$$

Write skeleton equations for the following reactions. a. ammonium phosphate(aq) + chromium(III) bromide(aq) \(\rightarrow\) ammonium bromide(aq) \(+\) chromium(III) phosphate(s) b. chromium(VI) hydroxide(s) \(\rightarrow\) chromium(VI) oxide(s) \(+\) water(l) c. aluminum(s) + copper(I) chloride(aq) \(\rightarrow\) aluminum chloride(aq) \(+\) copper(s) d. potassium iodide(aq) + mercury(I) nitrate(aq) \(\rightarrow\) potassium nitrate(aq) + mercury(I) iodide(s)

Write the skeleton equation and the balanced chemical equation for the reaction between iron and chlorine.

Write a chemical equation representing the decomposition of water into two gaseous products. What are the products?

Distinguish between an ionic compound and a molecular compound dissolved in water. Do all molecular compounds ionize when dissolved in water? Explain.

Classify the type of reactions that occur in aqueous solutions, and give an example to support your answer.

Explain how an equation can be balanced even if the number of reactant particles differs from the number of product particles.

Apply Describe the reaction of aqueous solutions of sodium sulfide and copper(II) sulfate, producing the precipitate copper(II) sulfide.

Predict A piece of aluminum metal is placed in aqueous KCl. Another piece of aluminum is placed in an aqueous AgNO \(_{3}\) solution. Explain why a chemical reaction does or does not occur in each instance.

Design an Experiment You suspect that the water in a lake close to your school might contain lead in the form of \(\mathrm{Pb}^{2+}(\) aq) ions. Formulate your suspicion as a hypothesis and design an experiment to test your theory. Write the net ionic equations for the reactions of your experiment. (Hint: In aqueous solution, \(P b^{2+}\) forms compounds that are solids with \(C l^{-}, B r^{-}, I^{-},\) and \(S O_{4}^{2-}\) ions.)

Apply Write the chemical equations and net ionic equations for each of the following reactions that might occur in aqueous solutions. If a reaction does not occur, write \(N R\) in place of the products. Magnesium phosphate precipitates in an aqueous solution. $$\begin{array}{l}{\text { a. } \mathrm{KNO}_{3}+\mathrm{CsCl} \rightarrow} \\\ {\text { b. } \mathrm{Ca}(\mathrm{OH})_{2}+\mathrm{KCN} \rightarrow} \\\ {\text { c. } \mathrm{Li}_{3} \mathrm{PO}_{4}+\mathrm{MgSO}_{4} \rightarrow} \\\ {\text { d. } \mathrm{HBrO}+\mathrm{NaOH} \rightarrow}\end{array}$$

Analyze Explain why a nail exposed to air forms rust, whereas the same nail exposed to a pure nitrogen environment does not form rust.

A single-replacement reaction occurs between copper and silver nitrate. When 63.5 \(\mathrm{g}\) of copper reacts with 339.8 \(\mathrm{g}\) of silver nitrate, 215.8 \(\mathrm{g}\) of silver is produced. Write a balanced chemical equation for this reaction. What other product formed? What is the mass of the second product?

Complete the following problems in scientific notation. Round off to the correct number of significant figures. (Chapter 2\()\) $$\begin{array}{l}{\text { a. }\left(5.31 \times 10^{-2} \mathrm{cm}\right) \times\left(2.46 \times 10^{5} \mathrm{cm}\right)} \\ {\text { b. }\left(6.42 \times 10^{-2} \mathrm{g}\right) \div\left(3.21 \times 10^{-3} \mathrm{g}\right)} \\ {\text { c. }\left(9.87 \times 10^{4} \mathrm{g}\right)-\left(6.2 \times 10^{3} \mathrm{g}\right)}\end{array}$$

Distinguish between a mixture, a solution, and a compound. (Chapter 3\()\)

Differentiate between electron configuration and electron-dot structure. (Chapter 5\()\)

Identify the elements by their electron configuration. (Chapter 5) $$\begin{array}{l}{\text { a. } 1 \mathrm{s}^{2} 2 \mathrm{s}^{2} 2 \mathrm{p}^{6} 3 \mathrm{s}^{2} 3 \mathrm{p}^{6} 4 \mathrm{s}^{2} 3 \mathrm{d}^{10} 4 \mathrm{p}^{5}} \\ {\text { b. }[\mathrm{Ne}] 3 \mathrm{s}^{2} 3 \mathrm{p}^{4}} \\ {\text { c. }[\mathrm{Xe}] 6 \mathrm{s}^{2}}\end{array}$$

Write the electron configuration for the element fitting each description. (Chapter 6\()\) a. a metalloid in group 13 b. a nonmetal in group \(15,\) period 3

Describe the formation of positive and negative ions. (Chapter 7\()\)

Write the formula for the compounds made from each of the following pairs of ions. (Chapter 7\()\) $$\begin{array}{l}{\text { a. copper (I) and sulfite }} \\ {\text { b. } \operatorname{tin}(\mathrm{IV}) \text { and fluoride }} \\ {\text { c. gold(III) and cyanide }} \\ {\text { d. lead(II) and sulfide }}\end{array}$$

Kitchen Chemistry Make a poster describing chemical reactions that occur in the kitchen.