Halogens and halide ions
Halogens and halide ions
Group 7 is also called Group 17 in modern numbering. Fluorine, chlorine, bromine and iodine are the halogens, and they exist as diatomic molecules such as Cl2Cl_2Cl2 and Br2Br_2Br2.
Step-by-step lessons on Edexcel AS Level Chemistry The elements of Group 7. Each one builds up to exam-style questions.