DP Chemistry (last assessment 2024)
Question 18M.2.hl.TZ1.a
| Date | May 2018 | Marks available | [Maximum mark: 2] | Reference code | 18M.2.hl.TZ1.a |
| Level | hl | Paper | 2 | Time zone | TZ1 |
| Command term | Outline | Question number | a | Adapted from | N/A |
a.
[Maximum mark: 2]
18M.2.hl.TZ1.a
Calcium carbonate reacts with hydrochloric acid.
CaCO3(s) + 2HCl(aq) → CaCl2(aq) + H2O(l) + CO2(g)
Outline two ways in which the progress of the reaction can be monitored. No practical details are required.
[2]
Markscheme
Any two of:
loss of mass «of reaction mixture/CO2»
«increase in» volume of gas produced
change of conductivity
change of pH
change in temperature
Do not accept “disappearance of calcium carbonate”.
Do not accept “gas bubbles”.
Do not accept “colour change” or “indicator”.
[2 marks]
