Acid mine drainage from an active coal mine can lower the pH of nearby aquatic ecosystems, mobilising toxic metals. The table below shows the concentration of dissolved aluminium ions in a forest creek at different pH levels:
| pH of creek water | Concentration of dissolved aluminium ions in μg\mu\text{g}μg per litre |
|---|---|
| 4.2 | 245.8 |
| 4.8 | 158.4 |
| 5.4 | 92.6 |
| 6.0 | 34.5 |
Calculate the percentage change in the concentration of dissolved aluminium ions when the pH of the creek water rises from 4.8 to 5.4. Give your answer to one decimal place and show your working.
