Halogen

Group 7 contains the halogens. The familiar members are fluorine, chlorine, bromine and iodine. They are non-metals, and each of their atoms has seven electrons in its outer shell.

Chlorine, bromine and iodine are halogens, found in Group 7 of the periodic table. Here, you need to recall two observable physical properties of each pure element at room temperature: its colour and whether it is a solid, liquid or gas.

Group 1 metals also react with oxygen to form oxides and with halogens to form salts called metal halides.

Group 7 is a column of non-metals called the halogens. Fluorine, chlorine, bromine and iodine have similar chemical behaviour because their atoms each have seven electrons in their outer shell.