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  2. Hydrofluoric acid - Wikipedia

    en.wikipedia.org/wiki/Hydrofluoric_acid

    Hydrofluoric acid is a solution of hydrogen fluoride (HF) in water.Solutions of HF are colorless, acidic and highly corrosive.A common concentration is 49% (48-52%) but there are also stronger solutions (e.g. 70%) and pure HF has a boiling point near room temperature.

  3. Water splitting - Wikipedia

    en.wikipedia.org/wiki/Water_splitting

    Other reaction products like H 2 O 2 or HO 2 remain minor. At the very high temperature of 3,000 °C (3,270 K; 5,430 °F) more than half of the water molecules are decomposed. At the very high temperature of 3,000 °C (3,270 K; 5,430 °F) more than half of the water molecules are decomposed.

  4. Free-energy relationship - Wikipedia

    en.wikipedia.org/wiki/Free-energy_relationship

    The Hammett equation predicts the equilibrium constant or reaction rate of a reaction from a substituent constant and a reaction type constant. The Edwards equation relates the nucleophilic power to polarisability and basicity. The Marcus equation is an example of a quadratic free-energy relationship (QFER). [citation needed]

  5. Hypofluorous acid - Wikipedia

    en.wikipedia.org/wiki/Hypofluorous_acid

    2 HOF → 2 HF + O 2. This reaction is catalyzed by water. [2] It was isolated in the pure form by passing F 2 gas over ice at −40 °C, rapidly collecting the HOF gas away from the ice, and condensing it: [2] F 2 + H 2 O → HOF + HF. The compound has been characterized in the solid phase by X-ray crystallography [1] as a bent molecule with

  6. Phase-transfer catalyst - Wikipedia

    en.wikipedia.org/wiki/Phase-transfer_catalyst

    In chemistry, a phase-transfer catalyst or PTC is a catalyst that facilitates the transition of a reactant from one phase into another phase where reaction occurs. Phase-transfer catalysis is a special form of catalysis and can act through homogeneous catalysis or heterogeneous catalysis methods depending on the catalyst used.

  7. Stefan problem - Wikipedia

    en.wikipedia.org/wiki/Stefan_problem

    At the interface between the phases (in the classical problem) the temperature is set to the phase change temperature. To close the mathematical system a further equation, the Stefan condition, is required. This is an energy balance which defines the position of the moving interface.

  8. Damköhler numbers - Wikipedia

    en.wikipedia.org/wiki/Damköhler_numbers

    Since the reaction rate determines the reaction timescale, the exact formula for the Damköhler number varies according to the rate law equation. For a general chemical reaction A → B following the Power law kinetics of n-th order , the Damköhler number for a convective flow system is defined as:

  9. Van 't Hoff equation - Wikipedia

    en.wikipedia.org/wiki/Van_'t_Hoff_equation

    The Van 't Hoff equation relates the change in the equilibrium constant, K eq, of a chemical reaction to the change in temperature, T, given the standard enthalpy change, Δ r H ⊖, for the process. The subscript r {\displaystyle r} means "reaction" and the superscript ⊖ {\displaystyle \ominus } means "standard".