pH & buffers worksheet with answers

Free printable pH & buffers worksheet: 6 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

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1.Easy
02468101214acidicneutralbasicpH = ?

Find the pH pH of a 0.1 mol/L solution of NaOH, a strong base, at 25 °C.

c = 0.1 mol/L
pH =
2.Easy
02468101214acidicneutralbasicpH = ?

Find the pH pH of a 0.25 mol/L solution of hydrochloric acid (HCl), a strong acid.

c = 0.25 mol/L
pH =
3.Medium
02468101214acidicneutralbasicpH = ?

Find the pH pH of a 0.5 mol/L solution of benzoic acid (Ka = 6.3 × 10⁻⁵).

c = 0.5 mol/LKa = 6.3 × 10⁻⁵
pH =
4.Medium
02468101214acidicneutralbasicpH = ?

Find the pH pH of a 0.25 mol/L solution of formic acid (Ka = 0.00018).

c = 0.25 mol/LKa = 0.00018
pH =
5.Hard
02468101214acidicneutralbasicpH = ?

A buffer contains 0.5 mol/L formic acid and 0.15 mol/L of its sodium salt. Ka = 0.00018. Find the pH pH of the buffer.

[HA] = 0.5[A⁻] = 0.15Ka = 0.00018
pH =
6.Hard
02468101214acidicneutralbasicpH = ?

A buffer contains 0.5 mol/L acetic acid and 0.8 mol/L of its sodium salt. Ka = 1.8 × 10⁻⁵. Find the pH pH of the buffer.

[HA] = 0.5[A⁻] = 0.8Ka = 1.8 × 10⁻⁵
pH =

Answer key

  1. 1. pH = 13
  2. 2. pH = 0.6021
  3. 3. pH = 2.253
  4. 4. pH = 2.179
  5. 5. pH = 3.222
  6. 6. pH = 4.949

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