Question 1: Define a strong acid and give one example.

Answer: A strong acid completely dissociates in water; example: hydrochloric acid (HCl).

Question 2: Explain the difference between a strong acid and a weak acid in terms of dissociation.

Answer: A strong acid fully dissociates into ions in water, while a weak acid only partially dissociates, resulting in fewer free ions.

Question 1: Calculate the pH of a 0.01 mol/L hydrochloric acid (HCl) solution. (Use pH = -log [H+])

Answer: pH = 2

Question 2: If a weak acetic acid solution has a concentration of 0.1 mol/L and an acid dissociation constant (Ka) of 1.8 x 10^-5, estimate the pH of the solution.

Answer: Approximately pH 3.

Question 1: Outline the procedure for testing which of two acids is stronger using pH indicators, and list at least two safety precautions.

Answer: To test acid strength, add equal volumes of each acid to separate test solutions and observe the color change of a pH indicator. The acid with the lower pH (more acidic) is stronger. Safety precautions include wearing gloves and eye protection to avoid contact with the acids and working in a well-ventilated area.

Question 1: A solution of sulfuric acid has a pH of 1.5. Is sulfuric acid considered a strong or weak acid? Explain your reasoning.

Answer: It is a strong acid because the low pH indicates high acidity and complete dissociation.

Question 2: If 50 mL of 0.1 mol/L hydrochloric acid reacts with a base and the pH of the resulting solution is 4.5, what can you infer about the acid's strength?

Answer: Since the pH is relatively high compared to strong acids, this suggests the acid is weak or has been neutralized significantly.

Question 1: Describe how the dissociation of strong and weak acids differs in water and how this affects their pH levels. (6 marks)

Answer: Strong acids completely dissociate into ions in water, producing a high concentration of H+ ions and resulting in a lower pH. Weak acids only partially dissociate, leading to fewer free H+ ions and a higher pH compared to strong acids of the same concentration.

Question 1: Explain why vinegar, which contains acetic acid, is considered a weak acid and discuss one practical use of vinegar in daily life.

Answer: Vinegar is a weak acid because it only partially dissociates in water. It is used in cooking for flavoring and as a preservative.