DP Chemistry (first assessment 2025)
Question 22M.1A.HL.TZ2.11
| Date | May 2022 | Marks available | [Maximum mark: 1] | Reference code | 22M.1A.HL.TZ2.11 |
| Level | HL | Paper | 1A | Time zone | TZ2 |
| Command term | Deduce | Question number | 11 | Adapted from | N/A |
11.
[Maximum mark: 1]
22M.1A.HL.TZ2.11
What is the formal charge of the oxygen atom in H3O+?
A. −2
B. −1
C. 0
D. +1
[1]
Markscheme
D
Examiners report
44% of candidates were able to determine the formal charge of the oxygen atom in H3O+. The most commonly chosen distractor was -2 (the oxidation state of the oxygen).
Syllabus sections
Structure 3. Classification of matter » Structure 3.1—The periodic table: Classification of elements » Structure 3.1.10—Transition element complexes are coloured due to the absorption of light when an electron is promoted between the orbitals in the split d-sublevels. The colour absorbed is complementary to the colour observed. Apply the colour wheel to deduce the wavelengths and frequencies of light absorbed and/or observed.