23 4.7 Neutralisation Reactions

Practice questions

1. 1. 1. 1. According to the Arrhenius definition, an acid is a compound that increases hydrogen ion concentration in an aqueous solution. True or false?
         2. According to the Arrhenius definition, a base is a compound that increases hydroxyl ion concentration in an aqueous solution. True or false?
         3. Predict the products of each acid-base combination listed. Assume that a neutralisation reaction occurs.
            1. 1. [latex]\ce{HCl +KOH {\rightarrow} ?}[/latex]
               2. [latex]\ce{H_{2}SO_{4} +KOH {\rightarrow} ?}[/latex]
               3. [latex]\ce{H_{3}PO_{4} + Ni{(OH)}_{2} {\rightarrow} ?}[/latex]
         4. Write a balanced chemical equation for the neutralisation reaction between each given acid and base. Include the proper phase labels.
            1. 1. [latex]\ce{HI {(aq)} +KOH {(aq)} {\rightarrow} ?}[/latex]
               2. [latex]\ce{H_{2}SO_{4} {(aq)} + Ba{(OH)}_{2} {(aq)} {\rightarrow} ?}[/latex]
         5. What is the balanced equation for the neutralisation reaction between [latex]\ce{HBr} {(aq)}[/latex] and [latex]\ce{Ba{(OH)}_{2}} {(aq)}[/latex]?
            1. 1. [latex]\ce{2HBr{(aq)} + Ba{(OH)}_{2}{(aq)} {\rightarrow} 2H_{2}O {(l)}+ BaBr_{2}{(aq)}}[/latex]
               2. [latex]\ce{2HBr{(aq)} + Ba{(OH)}_{2}{(aq)} {\rightarrow} H_{2}O {(l)} + BaBr_{2}{(aq)}}[/latex]
               3. [latex]\ce{2HBr{(aq)} + Ba{(OH)}_{2}{(aq)} {\rightarrow} 2H_{2}O {(l)} + Ba{(OH)}_{2}{(aq)}}[/latex]
               4. [latex]\ce{2HBr{(aq)} + Ba{(OH)}_{2}{(aq)} {\rightarrow} H_{3}O^{+} {(aq)}  + BaBr_{2}{(aq)}}[/latex]
         6. Write the net ionic equation for \ce{HI} {(aq)} and \ce{KOH} {(aq)}.
            1. 1. [latex]\ce{H^{+}{(aq)} + OH^{-}{(aq)} {\rightarrow} H_{2}O {(l)}}[/latex]
               2. [latex]\ce{HI{(aq)} + KOH{(aq)} {\rightarrow} H_{2}O {(l)} + KI{(s)}}[/latex]
               3. [latex]\ce{H^{+}{(aq)} + I^{-}{(aq)} + K^{+}{(aq)} + OH^{-}{(aq)} {\rightarrow} H_{2}O {(l)} + KI{(s)}}[/latex]
               4. [latex]\ce{H^{+}{(aq)} + OH^{-}{(aq)} + K^{+}{(aq)} {\rightarrow} H_{2}O {(l)} + I^{-}}[/latex]
         7. Write the balanced net ionic equation for neutralisation reaction between [latex]\ce{H_{2}SO_{4}{(aq)}}[/latex] and [latex]\ce{Ba{(OH)}_{2}{(aq)}}[/latex].
            1. 1. [latex]\ce{H^{+}{(aq)} + SO_{4}^{2-}{(aq)} + Ba^{2+}{(aq)} + OH^{-}{(aq)} {\rightarrow} BaSO_{4}{(s)} + H_{2}O{(l)}}[/latex]
               2. [latex]\ce{2H^{+}{(aq)} + SO_{4}^{2-}{(aq)} + Ba^{2+}{(aq)} + 2OH^{-}{(aq)} {\rightarrow} Ba{(s)} + SO_{4}^{2-}{(s)} + 2H_{2}O{(l)}}[/latex]
               3. [latex]\ce{H^{+}{(aq)} +  OH^{-}{(aq)} {\rightarrow} H_{2}O{(l)}}[/latex]
               4. [latex]\ce{2H^{+}{(aq)} + SO_{4}^{2-}{(aq)} + Ba^{2+}{(aq)} + 2OH^{-}{(aq)} {\rightarrow} BaSO_{4}{(s)}  + 2H_{2}O{(l)}}[/latex]
         8. Why is the net ionic equation for the neutralisation reaction between [latex]\ce{HCl} {(aq)}[/latex] and [latex]\ce{KOH} {(aq)}[/latex] the same as the net ionic equation for the neutralisation reaction between [latex]\ce{HNO_{3}{(aq)}}[/latex] and [latex]\ce{RbOH}[/latex]?
            1. 1. Because both reactions are acid-base neutralisation reactions.
               2. Because the salts are insoluble/solids in both cases.
               3. Because the salts are soluble in both cases, the net ionic reaction is just [latex]\ce{H^{+}{(aq)} + OH^{-}{(aq)} {\rightarrow} H_{2}O{(l)}}[/latex].
               4. Because [latex]\ce{H^{+}}[/latex] and [latex]\ce{OH^{-}}[/latex] are spectator ions in both cases.
         9. Write a balanced chemical equation for the neutralisation reaction between [latex]\ce{HNO_{3}}[/latex] and [latex]\ce{Fe{(OH)}_{3}}[/latex].
            1. 1. [latex]\ce{H^{+}{(aq)} + OH^{-}{(aq)} {\rightarrow} H_{2}O{(l)}}[/latex]
               2. [latex]\ce{3HNO_{3}{(aq)} + Fe{(OH)}_{3}{(aq)} {\rightarrow} Fe^{3+}{(aq)} + NO_{3}^{-}{(aq)} + 3H_{2}O{(l)}}[/latex]
               3. [latex]\ce{3HNO_{3}{(aq)} + Fe{(OH)}_{3}{(aq)} {\rightarrow} Fe{(NO_{3})}_{3}{(aq)} + 3H_{2}O{(l)}}[/latex]
               4. [latex]\ce{HNO_{3}{(aq)} + Fe{(OH)}_{3}{(aq)} {\rightarrow} Fe{(NO_{3})}_{3}{(aq)} + H_{2}O{(l)}}[/latex]
         10. Which of the following is a neutralisation reaction?
             1. 1. [latex]\ce{2NaHCO_{3}{(aq)} {\rightarrow} Na_{2}CO_{3}{(s)} + CO_{2}{(g)} + H_{2}O{(l)}}[/latex]
                2. [latex]\ce{Al{(OH)}_{3}{(aq)} + 3HNO_{3}{(aq)} {\rightarrow} Al{(NO_{3})}_{3}{(aq)} + 3H_{2}O{(l)}}[/latex]
                3. [latex]\ce{CH_{4}{(g)} + 2O_{2}{(g)} {\rightarrow} CO_{2}{(g)} + 2H_{2}O{(g)}}[/latex]
                4. [latex]\ce{Fe_{2}O_{3}{(s)} + 3CO{(g)} {\rightarrow} 2Fe{(s)} + 3CO_{2}{(g)}}[/latex]

Answers

1. 1. 1. True
      2. True
      3. Products are as follows:
         1. 1. [latex]\ce{KCl + H_{2}O}[/latex]
            2. [latex]\ce{K_{2}SO_{4} + H_{2}O}[/latex]
            3. [latex]\ce{Ni_{3}{(PO_{4})}_{2}}[/latex]
      4. Balanced chemical equations are as follows:
         1. 1. [latex]\ce{HCl +KOH {\rightarrow} KCl {(aq)} + H_{2}O {(l)}}[/latex]
            2. [latex]\ce{H_{2}SO_{4} {(aq)} + Ba{(OH)}_{2} {(aq)} {\rightarrow} BaSO_{4}{(s)} + 2H_{2}O {(l)}}[/latex]
      5. a
      6. a
      7. d
      8. c
      9. c
      10. b