DP Chemistry (last assessment 2024)
Question 18M.2.sl.TZ2.b.iii
| Date | May 2018 | Marks available | [Maximum mark: 1] | Reference code | 18M.2.sl.TZ2.b.iii |
| Level | sl | Paper | 2 | Time zone | TZ2 |
| Command term | Outline | Question number | b.iii | Adapted from | N/A |
b.iii.
[Maximum mark: 1]
18M.2.sl.TZ2.b.iii
Enthalpy changes depend on the number and type of bonds broken and formed.
The table lists the standard enthalpies of formation, , for some of the species in the reaction above.
Outline why the value of enthalpy of reaction calculated from bond enthalpies is less accurate.
[1]
Markscheme
«bond enthalpies» averaged values «over similar compounds»
OR
«bond enthalpies» are not specific to these compounds
[1 mark]
