O O− \\ / N+ | O−
A nitrate salt forms if a positively charged ion attaches to one of the negatively charged oxygen atoms of the nitrate ion.
Nitrates are also oxidizing agents. When mixed with hydrocarbons or carbohydrates, nitrates can form a flammable[?] or even explosive mixture. For example, potassium nitrate is the oxidizing ingredient in black gunpowder.
Nitrates covered in Wikipedia include: