DP Chemistry (first assessment 2025)
Question 19M.1A.SL.TZ1.20
| Date | May 2019 | Marks available | [Maximum mark: 1] | Reference code | 19M.1A.SL.TZ1.20 |
| Level | SL | Paper | 1A | Time zone | TZ1 |
| Command term | Question number | 20 | Adapted from | N/A |
20.
[Maximum mark: 1]
19M.1A.SL.TZ1.20
Which is not a source of oxides of sulfur and nitrogen?
A. burning coal
B. internal combustion engines
C. burning methane
D. volcanic eruptions
[1]
Markscheme
C
Examiners report
One teacher thought this was a tricky question if candidates did not think of impurities in the combustion. However, 64 % of candidates answered correctly.
Syllabus sections
Reactivity 3. What are the mechanisms of chemical change? » Reactivity 3.1—Proton transfer reactions » Reactivity 3.1.15—An appropriate indicator for a titration has an end point range that coincides with the pH at the equivalence point. Identify an appropriate indicator for a titration from the identity of the salt and the pH range of the indicator.