DP Chemistry (last assessment 2024)
Question 18N.3.hl.TZ0.b
| Date | November 2018 | Marks available | [Maximum mark: 2] | Reference code | 18N.3.hl.TZ0.b |
| Level | hl | Paper | 3 | Time zone | TZ0 |
| Command term | Suggest | Question number | b | Adapted from | N/A |
b.
[Maximum mark: 2]
18N.3.hl.TZ0.b
One way of classifying materials is based on the type of bonding present.
Structures of poly(methyl acrylate), PMA, and Bakelite® are shown.
Suggest, giving reasons, which is the thermoplastic polymer and which is the thermosetting polymer.
[2]
Markscheme
Thermoplastic polymer:
PMA AND «weak» intermolecular/IMFs/London/dispersion/van der Walls/vdW/dipole-dipole forces «between layers/chains»
OR
PMA AND no/few cross-links «between layers/chains» ✔
Thermosetting polymer:
Bakelite® AND «strong» covalent bonds «between layers/chains»
OR
Bakelite® AND extensive cross-links «between layers/chains» ✔
Do not accept “hydrogen bonding” for M1.
Award [1 max] for correct reasons for both polymer classes even if named polymers are incorrectly classified.