DP Chemistry (last assessment 2024)

Test builder »

Question 19M.3.hl.TZ2.13a

Select a Test
Date May 2019 Marks available [Maximum mark: 2] Reference code 19M.3.hl.TZ2.13a
Level hl Paper 3 Time zone TZ2
Command term Outline Question number a Adapted from N/A
a.
[Maximum mark: 2]
19M.3.hl.TZ2.13a

Hemoglobin contains heme groups with the porphyrin ring bound to an iron(II) ion.

(a)

Outline why the complex formed between Fe2+ and oxygen is red. Refer to the diagram above and section 17 of the data booklet.

[2]

Markscheme

extensive conjugated system
OR
extensive delocalized bonding system
OR
extended system of alternating double and single bonds  [✔]

absorbs green
OR
complementary to red light  [✔]

Examiners report

This part was fairly well answered with the majority of the candidates managed one mark. The second mark was missed because the candidates did not write extensive conjugated system or extensive delocalised bonding system.

Syllabus sections