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  2. Energy profile (chemistry) - Wikipedia

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

    Figure 6:Reaction Coordinate Diagrams showing reactions with 0, 1 and 2 intermediates: The double-headed arrow shows the first, second and third step in each reaction coordinate diagram. In all three of these reactions the first step is the slow step because the activation energy from the reactants to the transition state is the highest.

  3. Conversion (chemistry) - Wikipedia

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

    Conversion and its related terms yield and selectivity are important terms in chemical reaction engineering.They are described as ratios of how much of a reactant has reacted (X — conversion, normally between zero and one), how much of a desired product was formed (Y — yield, normally also between zero and one) and how much desired product was formed in ratio to the undesired product(s) (S ...

  4. Alkane metathesis - Wikipedia

    en.wikipedia.org/wiki/Alkane_metathesis

    These systems catalyze the conversion of ethane to give methane, propane and traces of butane. [1] Cross metathesis can also take place, for example methane and propane can react to give two molecules of ethane. Ethane reacts with toluene to give ethylbenzene and xylene. The reaction involves metallocyclobutane intermediates just as in olefin ...

  5. Ethane - Wikipedia

    en.wikipedia.org/wiki/Ethane

    Although ethane is a greenhouse gas, it is much less abundant than methane, has a lifetime of only a few months compared to over a decade, [30] and is also less efficient at absorbing radiation relative to mass. In fact, ethane's global warming potential largely results from its conversion in the atmosphere to methane. [31]

  6. Woodward–Hoffmann rules - Wikipedia

    en.wikipedia.org/wiki/Woodward–Hoffmann_rules

    Thermolysis converts 1 to (E,E) geometric isomer 2, but 3 to (E,Z) isomer 4.. The Woodward–Hoffmann rules (or the pericyclic selection rules) [1] are a set of rules devised by Robert Burns Woodward and Roald Hoffmann to rationalize or predict certain aspects of the stereochemistry and activation energy of pericyclic reactions, an important class of reactions in organic chemistry.

  7. Catalytic reforming - Wikipedia

    en.wikipedia.org/wiki/Catalytic_reforming

    A side reaction is hydrogenolysis, which produces light hydrocarbons of lower value, such as methane, ethane, propane and butanes. Continuous Catalytic reforming (CCR) unit In addition to a gasoline blending stock, reformate is the main source of aromatic bulk chemicals such as benzene , toluene , xylene and ethylbenzene , which have diverse ...

  8. Heat of combustion - Wikipedia

    en.wikipedia.org/wiki/Heat_of_combustion

    That is, the heat of combustion, ΔH° comb, is the heat of reaction of the following process: C c H h N n O o (std.) + (c + h ⁄ 4 - o ⁄ 2) O 2 (g) → c CO 2 (g) + h ⁄ 2 H 2 O (l) + n ⁄ 2 N 2 (g) Chlorine and sulfur are not quite standardized; they are usually assumed to convert to hydrogen chloride gas and SO 2 or SO

  9. Cracking (chemistry) - Wikipedia

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

    In steam cracking, a gaseous or liquid hydrocarbon feed like naphtha, LPG or ethane is diluted with steam and briefly heated in a furnace without the presence of oxygen. Typically, the reaction temperature is very high, at around 850 °C, but the reaction is only allowed to take place very briefly.