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A nitrite test is a standard component of a urinary test strip. A positive test for nitrites in the urine is called nitrituria. This test is commonly used in diagnosing urinary tract infections (UTIs). A positive nitrite test indicates that the cause of the UTI is a Gram-negative organism, most commonly Escherichia coli. The reason for nitrites ...
The Griess test is an analytical chemistry test which detects the presence of nitrite ion in solution. One of its most important uses is the determination of nitrite in drinking water . The Griess diazotization reaction, on which the Griess reagent relies, was first described in 1858 by Peter Griess .
To ensure consistency and repeatability, the methods use in the chemical analysis of water samples are often agreed and published at a national or state level. By convention these are often referred to as "Blue book". [4] [5] Certain analyses are performed in-field (e.g. pH, specific conductance) while others involve sampling and laboratory ...
Water purification combines a number of methods to produce potable or drinking water. Downstream processing refers to purification of chemicals, pharmaceuticals and food ingredients produced by fermentation or synthesized by plant and animal tissues, for example antibiotics, citric acid, vitamin E, and insulin.
Ultrapure water (UPW), high-purity water or highly purified water (HPW) is water that has been purified to uncommonly stringent specifications. Ultrapure water is a term commonly used in manufacturing to emphasize the fact that the water is treated to the highest levels of purity for all contaminant types, including: organic and inorganic compounds; dissolved and particulate matter; volatile ...
Note that the presence of nitrite ions will interfere with this test. [4] The overall reaction is the reduction of the nitrate ion to nitric oxide by iron(II), which is oxidised to iron(III), followed by the formation of nitrosyl ferrous sulfate between the nitric oxide and the remaining iron(II), where nitric oxide is reduced to NO −. [5]
The nitrite ion has the chemical formula NO − 2. Nitrite (mostly sodium nitrite) is widely used throughout chemical and pharmaceutical industries. [1] The nitrite anion is a pervasive intermediate in the nitrogen cycle in nature. The name nitrite also refers to organic compounds having the –ONO group, which are esters of nitrous acid.
In the laboratory, sodium nitrite can be used to destroy excess sodium azide. [86] [87] 2 NaN 3 + 2 NaNO 2 + 4 H + → 3 N 2 + 2 NO + 4 Na + + 2 H 2 O. Above 330 °C sodium nitrite decomposes (in air) to sodium oxide, nitric oxide and nitrogen dioxide. [88] 2 NaNO 2 → Na 2 O + NO + NO 2. Sodium nitrite can also be used in the production of ...