Reactivity with negative ions

Laboratory studies have been made of the thermodynamic stability of N03 (HN03)n clusters (21,22) and the reactivity of nitric acid (23) and sulfuric acid 1 24) with negative ions. 

The application of high tension (e.g. 20 kV, 0.5 MHz) in an evacuated system (0.2. .. 8 torr) causes the residual gas to form a highly ionized mixture of positive and negative ions, electrons, photons and neutral gas molecules. In the presence of active sorbents this plasma reacts with the chromatographically separated substances to eld reactive ions and radicals. 

Their unique characteristics are a result of their outer shells having seven electrons, and thus requiring only one electron to become complete. This -1 oxidation state makes them extremely reactive with both metals and some nonmetal elements that form negative ions, and they may form either ionic or covalent bonds. They can also form compounds with each other these binary compounds of the halogens are called halides. ... 

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