DP Chemistry (first assessment 2025)

Test builder »

Question 20N.1B.SL.TZ0.2e

Select a Test
Date November 2020 Marks available [Maximum mark: 2] Reference code 20N.1B.SL.TZ0.2e
Level SL Paper 1B Time zone TZ0
Command term Calculate Question number e Adapted from N/A
e.
[Maximum mark: 2]
20N.1B.SL.TZ0.2e
(e)

Calculate the percentage uncertainty and percentage error in the experimentally determined value of Kc for methanol.

[2]

Markscheme

Percentage uncertainty:
«0.4×1006.5=»6«%» ✔

Percentage error:
«6.5-5.35.3=»23«%» ✔

Award [1 max] if calculations are reversed OR if incorrect alcohol is used.

Examiners report

Many students scored both points and others at least one. Weaker students inverted the calculations.

Syllabus sections