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  2. Phenol - Wikipedia

    en.wikipedia.org/wiki/Phenol

    Phenol (also known as carbolic acid, phenolic acid, or benzenol) is an aromatic organic compound with the molecular formula C 6 H 5 OH. [5] It is a white crystalline solid that is volatile . The molecule consists of a phenyl group ( −C 6 H 5 ) bonded to a hydroxy group ( −OH ).

  3. Freshwater acidification - Wikipedia

    en.wikipedia.org/wiki/Freshwater_acidification

    Diagram depicting the sources and cycles of acid rain precipitation. Freshwater acidification occurs when acidic inputs enter a body of fresh water through the weathering of rocks, invasion of acidifying gas (e.g. carbon dioxide), or by the reduction of acid anions, like sulfate and nitrate within a lake, pond, or reservoir. [1]

  4. Phenols - Wikipedia

    en.wikipedia.org/wiki/Phenols

    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.

  5. Naturally occurring phenols - Wikipedia

    en.wikipedia.org/wiki/Naturally_occurring_phenols

    [1] [5] [6] [7]: 104 Some phenols are germicidal and are used in formulating disinfectants. Phenol – the simplest of the phenols Chemical structure of salicylic acid, the active metabolite of aspirin Chemical structure of aloe emodin, a diphenol Quercetin, a typical flavonoid, is a polyphenol Tannic acid, a typical polyphenol of indeterminate ...

  6. Acid rain - Wikipedia

    en.wikipedia.org/wiki/Acid_rain

    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 than this and ranges from 4–5 on average.

  7. Dow process (phenol) - Wikipedia

    en.wikipedia.org/wiki/Dow_process_(phenol)

    It is treated with aqueous sodium hydroxide at 350 °C and 300 bar or molten sodium hydroxide at 350 °C to convert it to sodium phenoxide, which yields phenol upon acidification. [2] When 1-[14 C]-1-chlorobenzene was subjected to aqueous NaOH at 395 °C, ipso substitution product 1-[14 C]-phenol was formed in 54% yield, while cine substitution ...

  8. Pechmann condensation - Wikipedia

    en.wikipedia.org/wiki/Pechmann_condensation

    For coumarins unsubstituted at the 4-position, the method requires the use of formylacetic acid or ester. These are unstable and not commercially available, but the acid may be produced in situ from malic acid and sulfuric acid above 100 °C. As soon as it forms, the formylacetic acid performs the Pechmann condensation.

  9. Raschig–Hooker process - Wikipedia

    en.wikipedia.org/wiki/Raschig–Hooker_process

    The main steps in this process are the production of chlorobenzene from benzene, hydrochloric acid and oxygen, and the subsequent hydrolysis of chlorobenzene to phenol. [4] The first step uses either a copper or iron chloride catalyst and exposes the materials to air at 200–250 °C.