change the nature, purpose, or function of something

the oxidation of ammonium compounds in dead organic material into nitrates and nitrites by soil bacteria (making nitrogen available to plants)

acid used especially in the production of fertilizers and explosives and rocket fuels

an unstable inorganic acid known only in solution and as nitrite salts

any compound containing the nitrate group (such as a salt or ester of nitric acid)

add oxygen to or combine with oxygen