DP Chemistry (last assessment 2024)
Question 19N.3.sl.TZ0.12a
| Date | November 2019 | Marks available | [Maximum mark: 1] | Reference code | 19N.3.sl.TZ0.12a |
| Level | sl | Paper | 3 | Time zone | TZ0 |
| Command term | Suggest | Question number | a | Adapted from | N/A |
a.
[Maximum mark: 1]
19N.3.sl.TZ0.12a
Octane number is a measure of the performance of engine fuel.
(a)
Suggest why a high-octane number fuel is preferable.
[1]
Markscheme
low knocking/auto-ignition
NOTE: Do not accept “pre-ignition”.
OR
more efficient fuel
NOTE: Accept “less CO2 emissions since knocking engine uses more fuel «to produce the same power»”.
OR
high compression
OR
more power extracted
OR
more air going into engine / turbocharging
OR
less engine damage ✔
