DP Chemistry (last assessment 2024)

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Question 17N.3.hl.TZ0.27

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Date November 2017 Marks available [Maximum mark: 2] Reference code 17N.3.hl.TZ0.27
Level hl Paper 3 Time zone TZ0
Command term Explain Question number 27 Adapted from N/A
27.
[Maximum mark: 2]
17N.3.hl.TZ0.27

Ethanol slows down the reaction time of a driver leading to traffic accidents. Explain how the concentration of ethanol in a sample of breath can be determined using a fuel cell breathalyser.

[2]

Markscheme

ethanol is oxidized «to ethanoic acid»

OR

electrons are released

current/potential proportional to concentration «of ethanol»

OR

current compared to a reference «to determine concentration»

Accept “ethanol reacts with oxygen” for M1.

Accept “voltage” for “potential”.

Syllabus sections