Which element is represented by the symbol 'I' that is a halogen?

The element represented by the symbol 'I' is iodine, which is a member of the halogen group in the periodic table. Halogens are known for their reactivity and are found in Group 17 (or VIIA) of the periodic table. Iodine is a non-metal element that exhibits typical properties of halogens, such as forming salts when it reacts with metals.

Iodine is unique among the halogens due to its relatively higher molecular weight and the fact that it can exist in a gaseous form or as a solid at room temperature, often appearing as a dark purple or nearly black solid. When heated, iodine sublimates to form a violet gas.

In contrast, the other elements listed do not belong to the halogen group. Xenon, krypton, and neon are all noble gases found in Group 18 of the periodic table, characterized by their lack of reactivity and stable electron configurations. Noble gases generally do not participate in chemical bonding in the way that halogens do. Thus, the choice of iodine accurately reflects both its elemental designation and its classification as a halogen.