DP Chemistry (last assessment 2024)
Question 18M.3.sl.TZ2.b
Date | May 2018 | Marks available | [Maximum mark: 1] | Reference code | 18M.3.sl.TZ2.b |
Level | sl | Paper | 3 | Time zone | TZ2 |
Command term | Outline | Question number | b | Adapted from | N/A |
b.
[Maximum mark: 1]
18M.3.sl.TZ2.b
One method of producing biodiesel is by a transesterification process.
Outline why the ester product of this reaction is a better diesel fuel than pentyl octanoate.
[1]
Markscheme
less viscous «and so does not need to be heated to flow»
OR
less likely to undergo incomplete combustion
OR
fewer intermolecular/London/dispersion forces
OR
vaporizes easier
Ignore equation and products in 14a.
Accept “van der Waals’/vdW” for “London”.
[1 mark]
