| Date | May 2015 | Marks available | 1 | Reference code | 15M.3.sl.TZ2.12 |
| Level | SL | Paper | 3 | Time zone | TZ2 |
| Command term | Suggest | Question number | 12 | Adapted from | N/A |
Question
Cholesteryl benzoate was one of the first liquid crystals studied.
Identify the structural feature of cholesteryl benzoate which makes it suitable for use as a liquid crystal.
Suggest the essential feature a liquid-crystal molecule must have so that the display can be turned “on” and “off”.
Markscheme
rigid / rod-shaped;
polar (group/molecule);
Examiners report
Many candidates knew the essential feature that a liquid-crystal molecule must have for the display being turned off and on but the description of the principles of a liquid-crystal display device was often poorly presented and not clearly understood.
Many candidates knew the essential feature that a liquid-crystal molecule must have for the display being turned off and on but the description of the principles of a liquid-crystal display device was often poorly presented and not clearly understood.
