In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

Q: One reactant for this reaction is best prepared by an S N 2 nucleophilic addition of a triphenyl compound, followed by elimination of the hydrogen halide by an organolithium reagent. This reaction itself proceeds through a rather unique intermediate formed when the pi electron from the reagents carbon-oxygen double bond migrates to the positively charged pole of one reactant; this intermediate is called a an oxaphosphetane, from which a triphenyl oxide is eliminated to complete the reaction. The aforementioned positively charged pole is on phosphorous because the aforementioned prepared reactant is a phosphorous ylide. For ten points, name this reaction that produces selectively double-bonded alkenes from aldehydes and phosphorous ylides and that is named for the German 1979 Chemistry Nobel winner.

A: Science
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Q: Instead of employing the Debye-Hull-Scherrer powder method, its namesakes relied on an array of atomic planes. Its namesakes built a vacuum apparatus and employed a hot filament, an accelerating electrode, and an arc-mounted Faraday box. A leak in the vacuum led its namesakes to heat the target, resulting in crystallized nickel, which gave startling results. A plot of collector current against beam energy was explained by constructive interference, and the results in general could be derived by combining Bragg's equation with the de Broglie wavelength for electrons. FTP name this experiment named for two physicists, which proved that electrons diffract.

A: Science
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Q: This author suggested that there is no other road to truth except through the "brook of fire," referring to this philosopher's admiration of the writings of Ludwig Feuerbach. This author satirizes Bastiat's theory of credit as an "utter poverty of ideas under a cover of formal logic" in his Grundrisse. In addition to writing Notes on James Mill and The Civil War in France, this theorist in perhaps his most famous work claims that the constant revolutionizing of production leads to a constant disturbance of social conditions thus "all that is solid melts into air, [and] all that is holy is profaned. " Also the author of the Critique of the Gotha Program, that quote comes from a work co-written by Friedrich Engels and warns of a specter haunting Europe. FTP name this German philosopher who discussed the class struggle between bourgeoisie and the proletariat in the Communist Manifesto.

A:
Social Science
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