DP Chemistry (last assessment 2024)
Question 18M.2.hl.TZ1.b
Date | May 2018 | Marks available | [Maximum mark: 1] | Reference code | 18M.2.hl.TZ1.b |
Level | hl | Paper | 2 | Time zone | TZ1 |
Command term | State | Question number | b | Adapted from | N/A |
b.
[Maximum mark: 1]
18M.2.hl.TZ1.b
Limescale, CaCO3(s), can be removed from water kettles by using vinegar, a dilute solution of ethanoic acid, CH3COOH(aq).
Dissolved carbon dioxide causes unpolluted rain to have a pH of approximately 5, but other dissolved gases can result in a much lower pH. State one environmental effect of acid rain.
[1]
Markscheme
Any one of:
corrosion of materials/metals/carbonate materials
destruction of plant/aquatic life
«indirect» effect on human health
Accept “lowering pH of oceans/lakes/waterways”.
[1 mark]
