Strong vs weak, dissociation extent：練習問題

Which of the following comparisons between \(0.1\text{ M}\) aqueous ammonia (\(NH_3\)) and \(0.1\text{ M}\) potassium hydroxide (\(KOH\)) at room temperature is correct?

Consider separate solutions of \(0.5 \text{ mol dm}^{-3}\) perchloric acid (\(HClO_4\), a strong acid) and \(0.5 \text{ mol dm}^{-3}\) hydrofluoric acid (\(HF\), a weak acid). Both are reacted with excess magnesium. Which of the following predictions is/are correct?

I. \(HClO_4\) produces a larger total volume of hydrogen gas than \(HF\).
II. The initial rate of reaction is slower for \(HF\) than for \(HClO_4\).
III. Both acids require the same volume of \(0.5 \text{ mol dm}^{-3} NaOH\) for complete neutralisation.

Which of the following statements correctly compares \(0.2\text{ M}\) propanoic acid (\(CH_3CH_2COOH\)) and \(0.2\text{ M}\) nitric acid (\(HNO_3\)) at the same temperature?

Consider two aqueous solutions at \(25 \text{ }^\circ\text{C}\), each with an initial concentration of \(0.1 \text{ mol dm}^{-3}\):
Solution P: Hydrochloric acid (HCl)
Solution Q: Ethanoic acid (CH\(_3\)COOH)

An equal volume of each solution is completely neutralised by adding sodium hydroxide solution.

Which of the following statements is INCORRECT regarding these solutions and their neutralisation?

Which of the following correctly describes the difference between \(0.1\text{ M}\) sulfuric acid (\(H_2SO_4\)) and \(0.1\text{ M}\) citric acid at the same temperature?

Consider two aqueous solutions, Solution P and Solution Q, both at \(25^\circ C\).

Solution P is \(0.0010 \text{ mol dm}^{-3}\) hydrochloric acid (HCl), a strong monoprotic acid.

Solution Q is \(0.0010 \text{ mol dm}^{-3}\) ethanoic acid (\(\text{CH}_3\text{COOH}\)), a weak monoprotic acid.

(a) Calculate the pH of Solution P. (Assume complete dissociation for HCl).

(b) Explain, in terms of dissociation, why hydrochloric acid is considered a strong acid and ethanoic acid is considered a weak acid.

(c) Compare the pH of Solution P and Solution Q. Briefly explain your answer.

Consider two aqueous solutions, Solution P and Solution Q, both at $$25^\circ C$$.

Solution P is $$0.10 \text{ mol dm}^{-3}$$ hydrochloric acid (HCl), a strong monoprotic acid.

Solution Q is $$0.10 \text{ mol dm}^{-3}$$ a weak monoprotic acid, HA. It is found that Solution Q has a pH of 3.00.

(a) Explain the difference between a strong acid and a weak acid in terms of their dissociation in aqueous solution.

(b) Calculate the pH of Solution P.

(c) For Solution Q, calculate:

(i) The concentration of hydrogen ions, $$[H^+(aq)]$$.

(ii) The acid dissociation constant, $$K_a$$, for HA.

(iii) The percentage dissociation of HA in Solution Q.

(d) If Solution Q is diluted by adding an equal volume of distilled water, explain how its percentage dissociation would change. Compare this effect with the dilution of Solution P.

(e) Describe and explain how Solution P and Solution Q would differ in terms of their electrical conductivity. Assume all other conditions are identical.