# Oxidizing Ability of the Group 17 Elements


Consider a reaction between one halogen—​chlorine, for example—and the ions of another—iodide, in this case. The iodide ions are dissolved from a salt such as sodium iodide or potassium iodide. The sodium or potassium ions are spectator ions and therefore irrelevant to the reaction, which proceeds as follows:

$Cl_2 + 2I^- \rightarrow 2Cl^- + I_2$

• The iodide ions lose electrons to form iodine molecules; they are oxidized.
• The chlorine molecules gain electrons to form chloride ions. They are reduced.

This is a redox reaction in which chlorine is acting as an oxidizing agent. The driving force force this reaction is straightforward to identify from the table of Standard Reduction Potentials (Table P2).

## Contributors and Attributions

• Jim Clark (ChemGuide)

This page titled Oxidizing Ability of the Group 17 Elements is shared under a CC BY-NC 4.0 license and was authored, remixed, and/or curated by Jim Clark.