Identifiers | |
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3D model (JSmol) | |
ChemSpider | |
ECHA InfoCard | 100.017.237 |
PubChem CID | |
UNII | |
CompTox Dashboard (EPA) | |
| |
Properties | |
C21H18O5S | |
Molar mass | 382.43 g·mol−1 |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Metacresol purple or m-cresol purple, also called m-cresolsulfonphthalein, is a triarylmethane dye and a pH indicator. It is used as a capnographic indicator for detecting detect end-tidal carbon dioxide to ensure successful tracheal intubation in an emergency. [1] [2] It can be used to measure the pH in subzero temperatures of saline or hypersaline media. [3]
In colorimetric capnography, the indicator is incorporated in an aqueous matrix that provides a pH just above the indicator's colour change. [4] When exposed to carbon dioxide (CO2), it undergoes a colour change from purple to yellow, because when CO2 dissolves in the matrix, it forms carbonic acid. [5]
In chemistry, it has two useful indicator ranges: [2]
Salinity is the saltiness or amount of salt dissolved in a body of water, called saline water. It is usually measured in g/L or g/kg.
Cresols are a group of aromatic organic compounds. They are widely-occurring phenols which may be either natural or manufactured. They are also categorized as methylphenols. Cresols commonly occur as either solids or liquids because their melting points are generally close to room temperature. Like other types of phenols, they are slowly oxidized by exposure to air, and the resulting impurities often give the samples a yellow to brownish red tint. Cresols have an odor characteristic to that of other simple phenols, reminiscent to some of a "coal tar" smell. The name "cresol" is an adduct of phenol and their traditional source, creosote.
Ninhydrin (2,2-dihydroxyindane-1,3-dione) is an organic compound with the formula C6H4(CO)2C(OH)2. It is used to detect ammonia and amines. Upon reaction with these amines, ninhydrin gets converted into deep blue or purple derivatives, which are called Ruhemann's purple. Ninhydrin is most commonly used to detect fingerprints, as the terminal amines of lysine residues in peptides and proteins sloughed off in fingerprints react with ninhydrin.
Capnography is the monitoring of the concentration or partial pressure of carbon dioxide (CO
2) in the respiratory gases. Its main development has been as a monitoring tool for use during anesthesia and intensive care. It is usually presented as a graph of CO
2 (measured in kilopascals, "kPa" or millimeters of mercury, "mmHg") plotted against time, or, less commonly, but more usefully, expired volume (known as volumetric capnography). The plot may also show the inspired CO
2, which is of interest when rebreathing systems are being used. When the measurement is taken at the end of a breath (exhaling), it is called "end tidal" CO
2 (PETCO2).
Toluene toxicity refers to the harmful effects caused by toluene on the body.
Haloarchaea are a class of the Euryarchaeota, found in water saturated or nearly saturated with salt. Halobacteria are now recognized as archaea rather than bacteria and are one of the largest groups. The name 'halobacteria' was assigned to this group of organisms before the existence of the domain Archaea was realized, and while valid according to taxonomic rules, should be updated. Halophilic archaea are generally referred to as haloarchaea to distinguish them from halophilic bacteria.
A carbon dioxide sensor or CO2 sensor is an instrument for the measurement of carbon dioxide gas. The most common principles for CO2 sensors are infrared gas sensors (NDIR) and chemical gas sensors. Measuring carbon dioxide is important in monitoring indoor air quality, the function of the lungs in the form of a capnograph device, and many industrial processes.
Carbon trioxide (CO3) is an unstable oxide of carbon (an oxocarbon). The possible isomers of carbon trioxide include ones with molecular symmetry point groups Cs, D3h, and C2v. The C2v state, consisting of a dioxirane, has been shown to be the ground state of the molecule. Carbon trioxide should not be confused with the stable carbonate ion (CO2−
3).
In chemistry, an oxocarbon or oxide of carbon is a chemical compound consisting only of carbon and oxygen. The simplest and most common oxocarbons are carbon monoxide (CO) and carbon dioxide. Many other stable or metastable oxides of carbon are known, but they are rarely encountered, such as carbon suboxide and mellitic anhydride.
A hydrogencarbonate indicator is a type of pH indicator that is sensitive enough to show a color change as the concentration of carbon dioxide gas in an aqueous solution increases. The indicator is used in photosynthesis and respiration experiments to find out whether carbon dioxide is being liberated. It is also used to test the carbon dioxide content during gaseous exchange of organisms. When the carbon dioxide content is higher than 0.04%, the initial red colour changes to yellow as the pH becomes more acidic. If the carbon dioxide content is lower than 0.04%, it changes from red to magenta and, in relatively very low carbon dioxide concentrations, to purple. Carbon dioxide, even in the concentrations found in exhaled air, will dissolve in the indicator to form carbonic acid, a weak acid, which will lower the pH and give the characteristic colour change. A colour change to purple during photosynthesis shows a reduction in the percentage of carbon dioxide and is sometimes inferred as production of oxygen, but there is not actually any direct evidence for it.
Carbon tetroxide or Oxygen carbonate(in its C2v isomer) is a highly unstable oxide of carbon with formula CO
4. It was proposed as an intermediate in the O-atom exchange between carbon dioxide and oxygen at high temperatures. The C2v isomer, which is 138 kJ mol−1 more stable than the D2d isomer, was first detected in electron-irradiated ices of carbon dioxide via infrared spectroscopy.
A soda lake or alkaline lake is a lake on the strongly alkaline side of neutrality, typically with a pH value between 9 and 12. They are characterized by high concentrations of carbonate salts, typically sodium carbonate, giving rise to their alkalinity. In addition, many soda lakes also contain high concentrations of sodium chloride and other dissolved salts, making them saline or hypersaline lakes as well. High pH and salinity often coincide, because of how soda lakes develop. The resulting hypersaline and highly alkalic soda lakes are considered some of the most extreme aquatic environments on Earth.
The oceanic carbon cycle is composed of processes that exchange carbon between various pools within the ocean as well as between the atmosphere, Earth interior, and the seafloor. The carbon cycle is a result of many interacting forces across multiple time and space scales that circulates carbon around the planet, ensuring that carbon is available globally. The Oceanic carbon cycle is a central process to the global carbon cycle and contains both inorganic carbon and organic carbon. Part of the marine carbon cycle transforms carbon between non-living and living matter.
o-Cresolphthalein is a phthalein dye used as a pH indicator in titrations. It is insoluble in water but soluble in ethanol. Its solution is colourless below pH 8.2, and purple above 9.8. Its molecular formula is C22H18O4. It is used medically to determine calcium levels in the human body, or to synthesize polyamides or polyimides.
Sea Ice Microbial Communities (SIMCO) refer to groups of microorganisms living within and at the interfaces of sea ice at the poles. The ice matrix they inhabit has strong vertical gradients of salinity, light, temperature and nutrients. Sea ice chemistry is most influenced by the salinity of the brine which affects the pH and the concentration of dissolved nutrients and gases. The brine formed during the melting sea ice creates pores and channels in the sea ice in which these microbes can live. As a result of these gradients and dynamic conditions, a higher abundance of microbes are found in the lower layer of the ice, although some are found in the middle and upper layers. Despite this extreme variability in environmental conditions, the taxonomical community composition tends to remain consistent throughout the year, until the ice melts.
Lake metabolism represents a lake's balance between carbon fixation and biological carbon oxidation. Whole-lake metabolism includes the carbon fixation and oxidation from all organism within the lake, from bacteria to fishes, and is typically estimated by measuring changes in dissolved oxygen or carbon dioxide throughout the day.
Dallol is a unique, terrestrial hydrothermal system around a cinder cone volcano in the Danakil Depression, northeast of the Erta Ale Range in Ethiopia. It is known for its unearthly colors and mineral patterns, and the very acidic fluids that discharge from its hydrothermal springs.
Laguna Negra is a lake in the Catamarca Province of Argentina. It lies on the Puna high plateau next to two other lakes and salt flats. The lake is less than 2 metres deep and forms a rough rectangle with a surface of 8.6 square kilometres (3.3 sq mi). Laguna Negra loses its water through evaporation, and is replenished through surface runoff and groundwater which ultimately originate to a large part from snowmelt. The waters of the lake are salty.
Colorimetric capnography or colorimetric capnometry is a technique of detecting CO2 in exhaled gas using a color changing device. Such devices usually incorporate pH paper which is designed to change colour with the acidity of CO2. These devices are placed in the breathing system, portable, do not require electricity, change reversibly (breath-by-breath), and have a small amount of dead space. They are commonly used for neonatal intubations in an emergency to confirm placement of an endotracheal tube, and rule out accidental oesophageal intubation.
Eatoniella mortoni is a species of marine gastropod mollusc in the family Eatoniellidae. First described by Winston Ponder in 1965, it is endemic to the waters of New Zealand. The species has been used to study the effects of ocean acidification, as it is known to thrive in carbon dioxide-rich environments.
Metacresol purple(pH indicator) | ||
below pH 7.4 | above pH 9.0 | |
7.4 | ⇌ | 9.0 |
Metacresol purple(pH indicator) | ||
below pH 1.2 | above pH 2.8 | |
1.2 | ⇌ | 2.8 |