10 minutes maximum

An IB Periodic Table is required.

1. The pH of a 0.024 mol dm-3 hydrochloric acid is:
• A.   0.6
• B.   1.6
• C.   2.4
• D.   3.2
2. The pH of a solution of 0.5 mol dm-3 barium hydroxide at a temperature of 298K is:
• A.   0
• B.   0.3
• C.   13.7
• D.   14.0
3. 10 cm3 of a pH 0.7 hydrochloric acid is diluted with distilled water, to a total volume of 1.0 dm3. What is the pH of the diluted acid?
• A.   -1.3
• B.   0.7
• C.   1.7
• D.   2.7
4. What is the concentration of H+(aq) ions in a nitric acid solution of pH 2.5?
• A.   0.0032 mol dm-3
• B.   0.032 mol dm-3
• C.   0.32 mol dm-3
• D.   2.5 mol dm-3
5. A solution of sulphuric acid has a pH = 2. What is the approximate pH of the solution when the acid is diluted 106 times?
• A.   2
• B.   5
• C.   7
• D.   8
6. At 50 oC, the ionic product constant of water Kw = 5.43 x 10-14. What is the pH of water at this temperature?
• A.   7.0
• B.   6.6
• C.   5.5
• D.   4.2

7. Which of the following solutions is acidic at 298 K?

 I.     [H+(aq)] = 3 x 10-4 mol dm-3 II.     [OH-(aq)] = 5.5 x 10-9 mol dm-3 III.     A solution with pH = 9.7

• A.   I and II only
• B.   II and III only
• C.   I only
• D.   I, II and III
8. Which of the following statements about acids is true?
• A.   An acid always has a pH of greater than 7.
• B.   Acid reacts with an alkali to make a salt and hydrogen.
• C.   Brønsted -Lowry acids are proton donors.
• D.   pH of a strong acid solution will decrease by 1 if the acid is diluted 10 times in volume.

9. 25 cm3 of 1.0 mol dm-3 hydrochloric acid is added to 25 cm3 of 0.4 mol dm-3 potassium hydroxide. What is the pH of the resulting solution?

 A. $$- log \big( {{25 \times 1.0 + 25 \times 0.4} \over{50}}\big)$$ B. $$- log \big( {{25 \times 1.0} \over{50}}\big)$$ C. $$- log \big( {{25 \times 0.4} \over{50}}\big)$$ D. $$- log \big( {{25 \times 1.0 - 25 \times 0.4} \over{50}}\big)$$
10. 30 cm3 of 1 mol dm-3 sodium hydroxide is added into 20 cm3 of 0.5 mol dm-3 hydrochloric acid.

NaOH + HCl   → NaCl + H2O

What is the pH of the resultant solution?

• A.   14.4
• B.   13.6
• C.   7.0
• D.   0.4