Home › TYS Solutions › O Level Chem › 2021 › P1 Q23

2021 O Level Chem P1 Q23 — Group VII / Halogens Solution

Group VII / Halogens 2021 O Level Pure Chemistry · Paper 1 · Q23

Question

Which statements about the Group VII elements are correct? 1 Bromine reacts with iodide ions to form iodine. 2 The elements become more reactive down the group. 3 Bromine is a liquid while iodine is a solid at room temperature.

A1, 2 and 3
B1 and 2 only
C1 and 3 only
D2 and 3 only

Correct answer: C

Video Solution

Explanation

Answer: C (1 and 3). Statement 1 is true: bromine is above iodine in Group VII and is more reactive, so it displaces iodine from iodide — Br₂ + 2I⁻ → 2Br⁻ + I₂.

Statement 2 is false: in Group VII the elements become less reactive down the group (oxidising power decreases from chlorine to bromine to iodine) — the opposite of Group I.

Statement 3 is true: at room temperature chlorine is a green gas, bromine is a red-brown liquid and iodine is a grey-black solid. So statements 1 and 3 are correct.

Get the Sec 3 / Sec 4 recording package

Every O Level Pure Chemistry TYS MCQ solution video, plus full Sec 3 / Sec 4 topic recordings.