DP Chemistry (first assessment 2025)

Test builder »

Question 19N.1B.SL.TZ0.1b(iii)

Select a Test
Date November 2019 Marks available [Maximum mark: 1] Reference code 19N.1B.SL.TZ0.1b(iii)
Level SL Paper 1B Time zone TZ0
Command term Suggest Question number b(iii) Adapted from N/A
b(iii).
[Maximum mark: 1]
19N.1B.SL.TZ0.1b(iii)
(b(iii))

Suggest a source of error in the procedure, assuming no human errors occurred and the balance was accurate.

[1]

Markscheme

surface area not uniform
NOTE: Accept “acids impure.

OR
limestone pieces do not have same composition/source
NOTE: Accept “«limestone» contains impurities”.

OR
limestone absorbed water «which increased mass»

OR
acid removed from solution when limestone removed
NOTE: Accept “loss of limestone when dried" OR "loss of limestone due to crumbling when removed from beaker”.

OR
«some» calcium sulfate deposited on limestone lost

OR
pieces of paper towel may have stuck to limestone

OR
beakers not covered/evaporation

OR
temperature was not controlled ✔

Syllabus sections