DP Chemistry (last assessment 2024)
Question 18N.2.hl.TZ0.6d
Date | November 2018 | Marks available | [Maximum mark: 2] | Reference code | 18N.2.hl.TZ0.6d |
Level | hl | Paper | 2 | Time zone | TZ0 |
Command term | Explain | Question number | d | Adapted from | N/A |
d.
[Maximum mark: 2]
18N.2.hl.TZ0.6d
Butanoic acid, CH3CH2CH2COOH, is a weak acid and ethylamine, CH3CH2NH2, is a weak base.
(d)
Explain why butanoic acid is a liquid at room temperature while ethylamine is a gas at room temperature.
[2]
Markscheme
Any two of:
butanoic acid forms more/stronger hydrogen bonds ✔
butanoic acid forms stronger London/dispersion forces ✔
butanoic acid forms stronger dipole–dipole interaction/force ✔
Accept “butanoic acid forms dimers”
Accept “butanoic acid has larger Mr/hydrocarbon chain/number of electrons” for M2.
Accept “butanoic acid has larger «permanent» dipole/more polar” for M3.
