From Mock A · Paper 1: Inorganic and Physical Chemistry
7.13 marks
Calculate the pH of 0.025 mol dm⁻³ barium hydroxide solution at 298 K (Kw = 1.00 × 10⁻¹⁴ mol² dm⁻⁶).
From Mock A · Paper 1: Inorganic and Physical Chemistry
7.24 marks
A buffer contains 0.10 mol of ethanoic acid and 0.050 mol of sodium ethanoate in 1.00 dm³. Ka = 1.74 × 10⁻⁵ mol dm⁻³. Calculate the pH.
From Mock A · Paper 1: Inorganic and Physical Chemistry
7.33 marks
0.010 mol of HCl is added to this buffer. Calculate the new pH.
From Mock A · Paper 1: Inorganic and Physical Chemistry
7.42 marks
Figure 1 shows the pH curve for ethanoic acid titrated with sodium hydroxide. Explain why phenolphthalein (range 8.3–10.0) is a suitable indicator but methyl orange (range 3.1–4.4) is not.
Figure 1
From Mock A · Paper 1: Inorganic and Physical Chemistry
7.52 marks
At 50 °C, Kw = 5.48 × 10⁻¹⁴ mol² dm⁻⁶. Calculate the pH of pure water at 50 °C and explain whether it is acidic.
From Mock A · Paper 3: Practical skills, all content and multiple choice
171 mark
What is the pH of 0.0010 mol dm⁻³ HCl?
From Mock B · Paper 1: Inorganic and Physical Chemistry
12.12 marks
Calculate the pH of 0.0500 mol dm⁻³ hydrochloric acid.
From Mock B · Paper 1: Inorganic and Physical Chemistry
12.23 marks
Calculate the pH of 0.100 mol dm⁻³ ethanoic acid. (Ka = 1.74 × 10⁻⁵ mol dm⁻³)
From Mock B · Paper 1: Inorganic and Physical Chemistry
12.33 marks
Calculate the pH of a buffer containing 0.100 mol dm⁻³ ethanoic acid and 0.150 mol dm⁻³ sodium ethanoate. (pKa = 4.76)
From Mock B · Paper 1: Inorganic and Physical Chemistry
12.42 marks
At 50 °C, Kw = 5.47 × 10⁻¹⁴ mol² dm⁻⁶. Calculate the pH of pure water at 50 °C and explain why the water is still neutral.
From Mock B · Paper 3: Practical skills, all content and multiple choice
75 marks
Ethanoic acid is titrated with sodium hydroxide. Explain the shape of the pH curve and choose a suitable indicator from methyl orange (pH 3.1–4.4) and phenolphthalein (pH 8.3–10.0).
From Mock B · Paper 3: Practical skills, all content and multiple choice
221 mark
What is the pH of 0.010 mol dm⁻³ NaOH at 298 K? (Kw = 1.0 × 10⁻¹⁴)
From Mock C · Paper 1: Inorganic and Physical Chemistry
12.13 marks
A weak acid HA has pH 2.70 at 0.100 mol dm⁻³. Calculate Ka.
From Mock C · Paper 1: Inorganic and Physical Chemistry
12.23 marks
Explain how an ethanoic acid / ethanoate buffer resists a change in pH when a small amount of alkali is added.
From Mock C · Paper 1: Inorganic and Physical Chemistry
12.32 marks
Calculate the pH after 25.0 cm³ of 0.200 mol dm⁻³ HCl is added to 25.0 cm³ of 0.100 mol dm⁻³ NaOH.
From Mock C · Paper 2: Organic and Physical Chemistry
15.23 marks
Calculate the pH of 0.0250 mol dm⁻³ Ba(OH)₂ at 298 K.
From Mock C · Paper 3: Practical skills, all content and multiple choice
3.13 marks
Describe how a pH meter is calibrated and used to follow a titration.
From Mock C · Paper 3: Practical skills, all content and multiple choice
3.23 marks
From a pH curve for a weak acid titrated with NaOH, the pH at half-neutralisation was 4.20. Explain how this gives Ka and calculate it.
From Mock C · Paper 3: Practical skills, all content and multiple choice
211 mark
Which is a Brønsted–Lowry base in HCl + NH₃ → NH₄⁺ + Cl⁻?
Score 0 / 49 · 0 of 19 marked
This paper is written by Plasmo in the style of the AQA A-Level Chemistry exam. It is not a past paper and is not produced or endorsed by the exam board.
Acids and bases Exam Questions: AQA A-Level Chemistry | Plasmo