Acidic oxide Some non-metal oxides, such as nitrous oxide (NO) and carbon monoxide (CO), do not display any acid/base characteristics. Acidic oxides can also react with basic oxides to produce salts of oxoanions: Acidic oxides are environmentally relevant. Sulfur and nitrogen oxides are considered air pollutants as they react with atmospheric water vapour to produce acid rain. Although it is difficult to classify these oxides as acids, the property is manifest in reactions with bases. For example, carbon dioxide reacts with alkali. For this reason, alkali is kept in stoppered vessels to inhibit reaction with atmospheric carbon dioxide. In geochemistry complex silicates
Nitrogen halogenating agents. Nitrogen forms nine molecular oxides, some of which were the first gases to be identified: NO (nitrous oxide), NO (nitric oxide), NO (dinitrogen trioxide), NO (nitrogen dioxide), NO (dinitrogen tetroxide), NO (dinitrogen pentoxide), NO (nitrosylazide), and N(NO) (trinitramide). All are thermally unstable towards decomposition to their elements. One other possible oxide that has not yet been synthesised is oxatetrazole (NO), an aromatic ring. Nitrous oxide (NO), better known as laughing gas, is made by thermal decomposition of molten ammonium nitrate at 250 °C. This is a redox reaction and thus nitric oxide and nitrogen are also produced as