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  2. Standard Gibbs free energy of formation - Wikipedia

    en.wikipedia.org/wiki/Standard_Gibbs_free_energy...

    The standard Gibbs free energy of formation (G f °) of a compound is the change of Gibbs free energy that accompanies the formation of 1 mole of a substance in its standard state from its constituent elements in their standard states (the most stable form of the element at 1 bar of pressure and the specified temperature, usually 298.15 K or 25 °C).

  3. Contact process - Wikipedia

    en.wikipedia.org/wiki/Contact_process

    The contact process is a method of producing sulfuric acid in the high concentrations needed for industrial processes. Platinum was originally used as the catalyst for this reaction; however, because it is susceptible to reacting with arsenic impurities in the sulfur feedstock, vanadium(V) oxide (V 2 O 5) has since been preferred.

  4. Sulfuric acid - Wikipedia

    en.wikipedia.org/wiki/Sulfuric_acid

    Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid (Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen, and hydrogen, with the molecular formula H 2 SO 4. It is a colorless, odorless, and viscous liquid that is miscible with water. [7] Structure ...

  5. Protonation - Wikipedia

    en.wikipedia.org/wiki/Protonation

    The complementary process, when a proton is removed from a Brønsted–Lowry acid, is deprotonation.) Some examples include The protonation of water by sulfuric acid: H 2 SO 4 + H 2 O ⇌ H 3 O + + HSO − 4; The protonation of isobutene in the formation of a carbocation: (CH 3) 2 C=CH 2 + HBF 4 ⇌ (CH 3) 3 C + + BF − 4

  6. Oleum - Wikipedia

    en.wikipedia.org/wiki/Oleum

    Oleum is produced in the contact process, where sulfur is oxidized to sulfur trioxide which is subsequently dissolved in concentrated sulfuric acid. [3] Sulfuric acid itself is regenerated by dilution of part of the oleum. The lead chamber process for sulfuric acid production was abandoned, partly because it could not produce sulfur trioxide or ...

  7. Standard enthalpy of formation - Wikipedia

    en.wikipedia.org/wiki/Standard_enthalpy_of_formation

    For many substances, the formation reaction may be considered as the sum of a number of simpler reactions, either real or fictitious. The enthalpy of reaction can then be analyzed by applying Hess' law, which states that the sum of the enthalpy changes for a number of individual reaction steps equals the enthalpy change of the overall reaction.

  8. Ammonium sulfate - Wikipedia

    en.wikipedia.org/wiki/Ammonium_sulfate

    A mixture of ammonia gas and water vapor is introduced into a reactor that contains a saturated solution of ammonium sulfate and about 2% to 4% of free sulfuric acid at 60 °C. Concentrated sulfuric acid is added to keep the solution acidic, and to retain its level of free acid. The heat of reaction keeps reactor temperature at 60 °C. Dry ...

  9. Mannheim process - Wikipedia

    en.wikipedia.org/wiki/Mannheim_process

    Sodium chloride and sulfuric acid are first fed onto a stationary reaction plate where an initial reaction takes place. The stationary plate is up to 6 m (20 ft) in diameter. Rotating rabble arms constantly turn over the mixture and move the intermediate product to a lower plate.