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  2. Dehydration reaction - Wikipedia

    en.wikipedia.org/wiki/Dehydration_reaction

    Alkenes can be made from alcohols by dehydration. This conversion, among others, is used in converting biomass to liquid fuels. [2] The conversion of ethanol to ethylene is a fundamental example: [3] [4] CH 3 CH 2 OH → H 2 C=CH 2 + H 2 O. The reaction is accelerated by acid catalysts such as sulfuric acid and certain zeolites.

  3. Loss on ignition - Wikipedia

    en.wikipedia.org/wiki/Loss_on_ignition

    Weigh the empty crucible that the sample is to be placed in and record its weight in a lab book. Place the sample in the empty crucible and weigh the crucible again with the sample in it. The new weight minus the empty crucible weight is the sample's wet weight. Place the sample in the drying oven or blast furnace as required.

  4. Elimination reaction - Wikipedia

    en.wikipedia.org/wiki/Elimination_reaction

    In accordance with an E2 elimination the reaction with t-butyl chloride results in a KIE of 2.3. The methyl chloride reaction (only S N 2 possible) on the other hand has a KIE of 0.85 consistent with a S N 2 reaction because in this reaction type the C-H bonds tighten in the transition state. The KIE's for the ethyl (0.99) and isopropyl (1.72 ...

  5. Zeisel determination - Wikipedia

    en.wikipedia.org/wiki/Zeisel_determination

    The ensuing reaction results in the cleavage of the ether or the ester into an alkyl iodide and respectively an alcohol or a carboxylic acid. Zeisel determination By heating this mixture, the gases are allowed to come into contact with a piece of paper higher up the test tube saturated with silver nitrate .

  6. Demethylation - Wikipedia

    en.wikipedia.org/wiki/Demethylation

    Demethylation often refers to cleavage of ethers, especially aryl ethers. [12]Historically, aryl methyl ethers, including natural products such as codeine (O-methylmorphine), have been demethylated by heating the substance in molten pyridine hydrochloride (melting point 144 °C (291 °F)) at 180 to 220 °C (356 to 428 °F), sometimes with excess hydrogen chloride, in a process known as the ...

  7. Extraction (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Extraction_(chemistry)

    [1] [2] Common extractants may be arranged in increasing order of polarity according to the Hildebrand solubility parameter: ethyl acetate < acetone < ethanol < methanol < acetone:water (7:3) < ethanol:water (8:2) < methanol:water (8:2) < water. Solid-liquid extractions at laboratory scales can use Soxhlet extractors. A solid sample containing ...

  8. Ether cleavage - Wikipedia

    en.wikipedia.org/wiki/Ether_cleavage

    Ether cleavage refers to chemical substitution reactions that lead to the cleavage of ethers. Due to the high chemical stability of ethers, the cleavage of the C-O bond is uncommon in the absence of specialized reagents or under extreme conditions. [1] [2] In organic chemistry, ether cleavage is an acid catalyzed nucleophilic substitution reaction.

  9. Ether - Wikipedia

    en.wikipedia.org/wiki/Ether

    A typical example of the first group is the solvent and anaesthetic diethyl ether, commonly referred to simply as "ether" (CH 3 −CH 2 −O−CH 2 −CH 3). Ethers are common in organic chemistry and even more prevalent in biochemistry , as they are common linkages in carbohydrates and lignin .