Question 20N.3.sl.TZ0.d
| Date | November 2020 | Marks available | [Maximum mark: 1] | Reference code | 20N.3.sl.TZ0.d |
| Level | sl | Paper | 3 | Time zone | TZ0 |
| Command term | Suggest | Question number | d | Adapted from | N/A |
Gasoline (petrol), biodiesel and ethanol are fuels.
[U.S. Department of Energy. https://afdc.energy.gov/]
A mixture of gasoline and ethanol is often used as a fuel. Suggest an advantage of such a mixture over the use of pure gasoline. Exclude any discussion of cost.
[1]
Any one:
uses up fossil fuels more slowly ✔
lower carbon footprint/CO2 emissions ✔
undergoes more complete combustion ✔
produces fewer particulates ✔
higher octane number/rating
OR
less knocking ✔
prevents fuel injection system build up
OR
helps keep engine clean ✔
Accept an example of a suitable advantage even if repeated from 9c.
Another question where many candidates obtained the mark. In quite a few cases students repeated the argument for (c) and this allowed them to get two points for the same answer.
