Inorganic compound (AgNO3), colourless, transparent crystals with a bitter, caustic, metallic taste. The most important silver compound, it is used to prepare other silver salts, to silver mirrors, and as a reagent in analysis. It is very soluble in water; dilute solutions are effective against gonococcal bacteria and may be applied to newborns' eyes to prevent blindness from gonorrhea. Ingesting silver nitrate causes violent abdominal pain and gastroenteritis.
Learn more about silver nitrate with a free trial on Britannica.com.
Any salt or ester of nitric acid (HNO3). The salts are inorganic compounds with ionic bonds, containing the nitrate ion (NO3−) and any cation. Many, particularly ammonium nitrate, are used as agricultural fertilizers (see saltpeter). Their runoff in surface water and groundwater can cause serious illness in humans. The esters are organic compounds with covalent bonds, having the structure RsinglehorzbondOsinglehorzbondNO2, in which R represents an organic combining group such as methyl, ethyl, or phenyl.
Learn more about nitrate with a free trial on Britannica.com.
In inorganic chemistry, a nitrate is a salt of nitric acid with an ion composed of one nitrogen and three oxygen atoms (NO3−). In organic chemistry the esters of nitric acid and various alcohols are called nitrates.
In organic chemistry a nitrate is a functional group with general chemical formula RONO2 where R stands for any organic residue. They are the esters of nitric acid and alcohols formed by nitroxylation. Examples are methyl nitrate formed by reaction of methanol and nitric acid, the nitrate of tartaric acid, and the inappropriately named nitroglycerin.
Infants, in particular, are especially sensitive to methemoglobinemia as a result of nitrate exposure. This is most often caused by high levels of nitrates in drinking water.
In most cases of excess nitrate concentrations in aquatic systems, the primary source is surface runoff from agricultural or landscaped areas which have received excess nitrate fertilizer. These levels of nitrate can also lead to algae blooms, and when nutrients become limiting (such as potassium, phosphate or nitrate) then eutrophication can occur. As well as leading to water anoxia, these blooms may cause other changes to ecosystem function, favouring some groups of organisms over others. Consequently, as nitrates form a component of total dissolved solids, they are widely used as an indicator of water quality.
Nitrates are also a by-product of septic systems. Specifically, they are a naturally occurring chemical that is left after the break down or decomposition of animal or human waste. Water quality may also be affected through ground water resources that have a high number of septic systems in a watershed. Septics leach down into ground water resources or aquifers and supply near by bodies of water. Lakes that rely on ground water are often affected by nitrification through this process.