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In biochemistry, naturally occurring phenols are natural products containing at least one phenol functional group. [1][2][3] Phenolic compounds are produced by plants and microorganisms. [4] Organisms sometimes synthesize phenolic compounds in response to ecological pressures such as pathogen and insect attack, UV radiation and wounding. [5]
Phenolphthalein (/ fɛˈnɒl (f) θəliːn / [citation needed]feh-NOL (F)-thə-leen) is a chemical compound with the formula C 20 H 14 O 4 and is often written as " HIn ", " HPh ", " phph " or simply " Ph " in shorthand notation. Phenolphthalein is often used as an indicator in acid–base titrations. For this application, it turns colorless in ...
Jizera Mountains in Central Europe in 2006 Tree dieback because of persistent drought in the Saxonian Vogtland in 2020. Forest dieback (also "Waldsterben", a German loan word, pronounced [ˈvaltˌʃtɛʁbn̩] ⓘ) is a condition in trees or woody plants in which peripheral parts are killed, either by pathogens, parasites or conditions like acid rain, drought, [1] and more.
Acid clouds can grow on SO 2 emissions from refineries, as seen here in Curaçao. Acid rain is rain or any other form of precipitation that is unusually acidic, meaning that it has elevated levels of hydrogen ions (low pH). Most water, including drinking water, has a neutral pH that exists between 6.5 and 8.5, but acid rain has a pH level lower ...
Polyphenols (/ ˌpɒliˈfiːnoʊl, - nɒl /) are a large family of naturally occurring phenols. [ 1 ] They are abundant in plants and structurally diverse. [ 1 ][ 2 ][ 3 ] Polyphenols include phenolic acids, flavonoids, tannic acid, and ellagitannin, some of which have been used historically as dyes and for tanning garments.
Phenol is readily alkylated at the ortho positions using alkenes in the presence of a Lewis acid such as aluminium phenoxide: [citation needed] CH 2 =CR 2 + C 6 H 5 OH → R 2 CHCH 2 -2-C 6 H 4 OH More than 100,000 tons of tert-butyl phenols are produced annually (year: 2000) in this way, using isobutylene (CH 2 =CMe 2 ) as the alkylating agent.
Soil acidification is the buildup of hydrogen cations, which reduces the soil pH. Chemically, this happens when a proton donor gets added to the soil. The donor can be an acid, such as nitric acid, sulfuric acid, or carbonic acid. It can also be a compound such as aluminium sulfate, which reacts in the soil to release protons.
Animation of a strong acid–strong base neutralization titration (using phenolphthalein). The equivalence point is marked in red. In chemistry, neutralization or neutralisation (see spelling differences) is a chemical reaction in which acid and a base react with an equivalent quantity of each other. In a reaction in water, neutralization ...