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Differentiate between the terms strength and concentration as they apply to acids and bases. When is \(\mathrm{HCl}\) strong? Weak? Concentrated? Dilute? Answer the same questions for ammonia. Is the conjugate base of a weak acid a strong base?

Consider a solution prepared by mixing a weak acid HA and \(\mathrm{HCl}\). What are the major species? Explain what is occurring in solution. How would you calculate the \(\mathrm{pH}\) ? What if you added NaA to this solution? Then added \(\mathrm{NaOH}\) ?

Explain why salts can be acidic, basic, or neutral, and show examples. Do this without specific numbers.

Consider a solution prepared by mixing a weak acid HA, HCl, and NaA. Which of the following statements best describes what happens? a. The \(\mathrm{H}^{+}\) from the \(\mathrm{HCl}\) reacts completely with the \(\mathrm{A}^{-}\) from the NaA. Then the HA dissociates somewhat. b. The \(\mathrm{H}^{+}\) from the \(\mathrm{HCl}\) reacts somewhat with the \(\mathrm{A}^{-}\) from the NaA to make HA, while the HA is dissociating. Eventually you have equal amounts of everything. c. The \(\mathrm{H}^{+}\) from the \(\mathrm{HCl}\) reacts somewhat with the \(\mathrm{A}^{-}\) from the NaA to make HA while the HA is dissociating. Eventually all the reactions have equal rates. d. The \(\mathrm{H}^{+}\) from the \(\mathrm{HCl}\) reacts completely with the \(\mathrm{A}^{-}\) from the NaA. Then the HA dissociates somewhat until "too much" \(\mathrm{H}^{+}\) and \(\mathrm{A}^{-}\) are formed, so the \(\mathrm{H}^{+}\) and \(\mathrm{A}^{-}\) react to form HA, and so on. Eventually equilibrium is reached. Justify your choice, and for choices you did not pick, explain what is wrong with them.

Is the conjugate base of a weak acid a strong base? Explain. Explain why \(\mathrm{Cl}^{-}\) does not affect the \(\mathrm{pH}\) of an aqueous solution.

The salt BX, when dissolved in water, produces an acidic solution. Which of the following could be true? (There may be more than one correct answer.) a. The acid \(\mathrm{HX}\) is a weak acid. b. The acid \(\mathrm{HX}\) is a strong acid. c. The cation \(\mathrm{B}^{+}\) is a weak acid. Explain.

Which of the following conditions indicate a basic solution at \(25^{\circ} \mathrm{C} ?\) a. \(\mathrm{pOH}=11.21\) b. \(\mathrm{pH}=9.42\) c. \(\left[\mathrm{OH}^{-}\right]>\left[\mathrm{H}^{+}\right]\) d. \(\left[\mathrm{OH}^{-}\right]>1.0 \times 10^{-7} M\)

Give three example solutions that fit each of the following descriptions. a. a strong electrolyte solution that is very acidic b. a strong electrolyte solution that is slightly acidic c. a strong electrolyte solution that is very basic d. a strong electrolyte solution that is slightly basic e. a strong electrolyte solution that is neutral

Write balanced equations that describe the following reactions. a. the dissociation of perchloric acid in water b. the dissociation of propanoic acid \(\left(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CO}_{2} \mathrm{H}\right)\) in water c. the dissociation of ammonium ion in water

For each of the following aqueous reactions, identify the acid, the base, the conjugate base, and the conjugate acid. a. \(\mathrm{H}_{2} \mathrm{O}+\mathrm{H}_{2} \mathrm{CO}_{3} \rightleftharpoons \mathrm{H}_{3} \mathrm{O}^{+}+\mathrm{HCO}_{3}^{-}\) b. \(\mathrm{C}_{5} \mathrm{H}_{5} \mathrm{NH}^{+}+\mathrm{H}_{2} \mathrm{O} \rightleftharpoons \mathrm{C}_{5} \mathrm{H}_{5} \mathrm{~N}+\mathrm{H}_{3} \mathrm{O}^{+}\) c. \(\mathrm{HCO}_{3}^{-}+\mathrm{C}_{5} \mathrm{H}_{5} \mathrm{NH}^{+} \rightleftharpoons \mathrm{H}_{2} \mathrm{CO}_{3}+\mathrm{C}_{5} \mathrm{H}_{5} \mathrm{~N}\)