Problem 14
Classify these aqueous solutions as acidic, neutral, or basic. a. \(\mathrm{HI}(a q)\) b. \(\mathrm{NaCl}(a q)\) c. \(\mathrm{NH}_{4} \mathrm{OH}(a q)\) d. \(\left[\mathrm{H}^{+}\right]=1 \times 10^{-8} \mathrm{M}\) e. \(\left[\mathrm{OH}^{-}\right]=1 \times 10^{-2} \mathrm{M}\) f. \(\left[\mathrm{H}^{+}\right]=5 \times 10^{-7} \mathrm{M}\) g. \(\left[\mathrm{OH}^{-}\right]=1 \times 10^{-12} \mathrm{M}\)
Problem 16
Which of these has the lowest concentration of hydrogen ions: \(0.1 \mathrm{M} \mathrm{HCl}, 0.1 \mathrm{M} \mathrm{NaOH}, 0.1 \mathrm{M} \mathrm{H}_{2} \mathrm{SO}_{4}\), or pure water? Explain your answer.
Problem 18
Assume that coal can be represented by the chemical formula \(\mathrm{C}_{135} \mathrm{H}_{96} \mathrm{O}_{9} \mathrm{NS}\). a. What is the percent of nitrogen by mass in coal? b. If 3 tons of coal is burned, what mass of nitrogen in the form of NO is produced? Assume that all of the nitrogen in the coal is converted to NO. c. Actually more NO is produced than you just calculated. Explain.
Problem 19
In 2006, the United States burned about \(1.1\) billion tons of coal. Assuming that it was \(2 \%\) sulfur by weight, calculate the tons of sulfur dioxide emitted.
Problem 20
Acid rain can damage marble statues and limestone building materials. Write a balanced chemical equation using an acid of your choice.
Problem 22
A garden product called dolomite lime is composed of tiny chips of limestone that contain both calcium carbonate and magnesium carbonate. This product is "intended to help the gardener correct the \(\mathrm{pH}\) of acid soils," as it is "a valuable source of calcium and magnesium." a. Is the "calcium" in the form of calcium ion or calcium metal? b. Write a chemical equation that shows why limestone "corrects" the pH of acidic soils. c. Will the addition of dolomite lime to soils cause the \(\mathrm{pH}\) to rise or fall? d. Plants such as rhododendrons, azaleas, and camellias should not be given dolomite lime. Explain.
Problem 27
a. On the label of a shampoo bottle, what does the phrase "pH-balanced" imply? b. Does the phrase "pH-balanced" influence your decision to buy a particular shampoo? Explain.
Problem 28
Judging by the taste, do you think there are more hydrogen ions in a glass of orange juice or in a glass of milk? Explain your reasoning.
Problem 29
The formula for acetic acid, the acid present in vinegar, is commonly written as \(\mathrm{HC}_{2} \mathrm{H}_{3} \mathrm{O}_{2}\). Many chemists write the formula as \(\mathrm{CH}_{3} \mathrm{COOH}\). a. Draw the Lewis structure for acetic acid. b. Show that both formulas represent acetic acid. c. What are the advantages and disadvantages of each formula? d. How many hydrogen atoms can be released as hydrogen ions per acetic acid molecule? Explain.
Problem 30
Television and magazine advertisements tout the benefits of antacids. A friend suggests that a good way to get rich quickly would be to market "antibase" tablets. Explain to your friend the purpose of antacids and offer some advice about the potential success of "antibase" tablets.
