Question 17N.3.hl.TZ0.b
| Date | November 2017 | Marks available | [Maximum mark: 2] | Reference code | 17N.3.hl.TZ0.b |
| Level | hl | Paper | 3 | Time zone | TZ0 |
| Command term | Outline | Question number | b | Adapted from | N/A |
A fuel cell converts chemical energy directly to electrical energy.
Outline one advantage and one disadvantage of the methanol cell (DMFC) compared with a hydrogen-oxygen fuel cell.
[2]
Advantage:
Any one of:
liquid methanol is easier to transport/store than gaseous hydrogen
OR
hydrogen is explosive
longer membrane life «as it operates in aqueous environment»
methanol has greater energy density than hydrogen
Disadvantage:
Any one of:
lower voltage
lower power per unit mass «of the cell»
lower efficiency
toxic/can be mistaken for ethanol
lower specific energy
Ignore any cost references throughout.
Accept “CO2/greenhouse gas produced” OR “requires a more highly efficient catalyst”.
Do not award marks for converse statements for the advantage and disadvantage.