DP Chemistry (last assessment 2024)
Question 20N.3.sl.TZ0.4e
Date | November 2020 | Marks available | [Maximum mark: 1] | Reference code | 20N.3.sl.TZ0.4e |
Level | sl | Paper | 3 | Time zone | TZ0 |
Command term | Justify | Question number | e | Adapted from | N/A |
e.
[Maximum mark: 1]
20N.3.sl.TZ0.4e
There has been significant growth in the use of carbon nanotubes, CNT.
(e)
Experiments have been done to explore the nematic liquid crystal behaviour of CNT. Justify how CNT molecules could be classified as nematic.
[1]
Markscheme
rod-shaped molecules
OR
«randomly distributed but» generally align
OR
no positional order AND have «some» directional order/pattern ✔
Accept “linear” for “rod-shaped”.
Examiners report
This was a very popular option with approximately 34% of candidates attempting Option B. Many students appeared well prepared for this option. Some candidates continue to provide answers with a heavy Biology bias that often make them lose valuable points.
