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  2. Vapor etching - Wikipedia

    en.wikipedia.org/wiki/Vapor_etching

    The HF reacts with the silanol groups and forms SiF 4 and H 2 O according to the following reaction. Si(OH) 4 + 4 HF → SiF 4 + 4 H 2 O. The etch process commonly takes place at reduced pressures, to promote the desorption of the reaction products. Water is formed during the etch reaction.

  3. 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.

  4. Thermochemical equation - Wikipedia

    en.wikipedia.org/wiki/Thermochemical_equation

    In thermochemistry, a thermochemical equation is a balanced chemical equation that represents the energy changes from a system to its surroundings. One such equation involves the enthalpy change, which is denoted with Δ H {\displaystyle \Delta H} In variable form, a thermochemical equation would appear similar to the following:

  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. Heterogeneous catalysis - Wikipedia

    en.wikipedia.org/wiki/Heterogeneous_catalysis

    Heterogeneous catalysis typically involves solid phase catalysts and gas phase reactants. [2] In this case, there is a cycle of molecular adsorption, reaction, and desorption occurring at the catalyst surface. Thermodynamics, mass transfer, and heat transfer influence the rate (kinetics) of reaction.

  7. 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]

  8. Self-ionization of water - Wikipedia

    en.wikipedia.org/wiki/Self-ionization_of_water

    The inverse recombination reaction H 3 O + + OH − → 2 H 2 O. is among the fastest chemical reactions known, with a reaction rate constant of 1.3 × 10 11 M −1 s −1 at room temperature. Such a rapid rate is characteristic of a diffusion-controlled reaction, in which the rate is limited by the speed of molecular diffusion. [15]

  9. Rate equation - Wikipedia

    en.wikipedia.org/wiki/Rate_equation

    In chemistry, the rate equation (also known as the rate law or empirical differential rate equation) is an empirical differential mathematical expression for the reaction rate of a given reaction in terms of concentrations of chemical species and constant parameters (normally rate coefficients and partial orders of reaction) only. [1]