What this tests
Syllabus point 8.3 — Group VII properties, in The Periodic Table. Difficulty easy (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 · 8.3 Group VII properties
June 2010 · Paper 11 · Question 26
One real Cambridge question from The Periodic Table, with the official answer. Cambridge has printed this question 3 times.