DP Chemistry (last assessment 2024)
Question 21M.2.hl.TZ2.b(iv)
| Date | May 2021 | Marks available | [Maximum mark: 3] | Reference code | 21M.2.hl.TZ2.b(iv) |
| Level | hl | Paper | 2 | Time zone | TZ2 |
| Command term | Sketch | Question number | b(iv) | Adapted from | N/A |
b(iv).
[Maximum mark: 3]
21M.2.hl.TZ2.b(iv)
Limestone can be converted into a variety of useful commercial products through the lime cycle. Limestone contains high percentages of calcium carbonate, CaCO3.
Thermodynamic data for the decomposition of calcium carbonate is given.
Sketch an energy profile for the decomposition of calcium carbonate based on your answer to b(i), labelling the axes and activation energy, Ea.
[3]
Markscheme
endothermic sketch ✓
x-axis labelled “extent of reaction/progress of reaction/reaction coordinate/reaction pathway” AND y-axis labelled “potential energy/energy/enthalpy✓
activation energy/Ea ✓
Do not accept “time” for x-axis.