What this tests
Syllabus point 10.2 — Fertilisers, in Chemistry of the environment. Difficulty medium (estimated from the question's demands, not a Cambridge rating).
Also set in
The same question, as Cambridge printed it in other papers.
Cambridge IGCSE Chemistry 0620 · 10.2 Fertilisers
June 2010 · Paper 13 · Question 33
One real Cambridge question from Chemistry of the environment, with the official answer. Cambridge has printed this question 3 times.