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  2. 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 ...

  3. Kjeldahl method - Wikipedia

    en.wikipedia.org/wiki/Kjeldahl_method

    Hot concentrated sulfuric acid oxidizes carbon (as bituminous coal) and sulfur (see sulfuric acid's reactions with carbon): C + 2 H 2 SO 4 → CO 2 + 2 SO 2 + 2 H 2 O S + 2 H 2 SO 4 → 3 SO 2 + 2 H 2 O. Catalysts like selenium, Hg 2 SO 4 or CuSO 4 are often added to make the digestion go faster. Na 2 SO 4 or K 2 SO 4 is also added to increase ...

  4. Acid–base reaction - Wikipedia

    en.wikipedia.org/wiki/Acid–base_reaction

    In chemistry, an acid–base reaction is a chemical reaction that occurs between an acid and a base.It can be used to determine pH via titration.Several theoretical frameworks provide alternative conceptions of the reaction mechanisms and their application in solving related problems; these are called the acid–base theories, for example, Brønsted–Lowry acid–base theory.

  5. Protonation - Wikipedia

    en.wikipedia.org/wiki/Protonation

    In chemistry, protonation (or hydronation) is the adding of a proton (or hydron, or hydrogen cation), usually denoted by H +, to an atom, molecule, or ion, forming a conjugate acid. [1] (The complementary process, when a proton is removed from a Brønsted–Lowry acid, is deprotonation.) Some examples include The protonation of water by ...

  6. Neutralization (chemistry) - Wikipedia

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

    The same equation relating the concentrations of acid and base applies. The concept of neutralization is not limited to reactions in solution. For example, the reaction of limestone with acid such as sulfuric acid is also a neutralization reaction. [Ca,Mg]CO 3 (s) + H 2 SO 4 (aq) → (Ca 2+, Mg 2+)(aq) + SO 2− 4 (aq) + CO 2 (g) + H 2 O

  7. Piranha solution - Wikipedia

    en.wikipedia.org/wiki/Piranha_solution

    The first and faster [citation needed] process is the removal of hydrogen and oxygen as units of water by the concentrated sulfuric acid. This occurs because hydration of concentrated sulfuric acid is strongly thermodynamically favorable, with a standard enthalpy of reaction of −880 kJ/mol.

  8. Ammonia - Wikipedia

    en.wikipedia.org/wiki/Ammonia

    The amount of ammonia in ammonium salts can be estimated quantitatively by distillation of the salts with sodium (NaOH) or potassium hydroxide (KOH), the ammonia evolved being absorbed in a known volume of standard sulfuric acid and the excess of acid then determined volumetrically; or the ammonia may be absorbed in hydrochloric acid and the ...

  9. Ammonium persulfate - Wikipedia

    en.wikipedia.org/wiki/Ammonium_persulfate

    Ammonium persulfate is prepared by electrolysis of a cold concentrated solution of either ammonium sulfate or ammonium bisulfate in sulfuric acid at a high current density. [2] [3] The method was first described by Hugh Marshall. [4]