DP Chemistry (last assessment 2024)
Question 18M.2.sl.TZ1.d
| Date | May 2018 | Marks available | [Maximum mark: 1] | Reference code | 18M.2.sl.TZ1.d |
| Level | sl | Paper | 2 | Time zone | TZ1 |
| Command term | Justify, Predict | Question number | d | Adapted from | N/A |
d.
[Maximum mark: 1]
18M.2.sl.TZ1.d
Urea, (H2N)2CO, is excreted by mammals and can be used as a fertilizer.
Urea can also be made by the direct combination of ammonia and carbon dioxide gases.
2NH3(g) + CO2(g) (H2N)2CO(g) + H2O(g) ΔH < 0
Predict, with a reason, the effect on the equilibrium constant, Kc, when the temperature is increased.
[1]
Markscheme
«Kc» decreases AND reaction is exothermic
OR
«Kc» decreases AND ΔH is negative
OR
«Kc» decreases AND reverse/endothermic reaction is favoured
[1 mark]
