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  2. Sulfate - Wikipedia

    en.wikipedia.org/wiki/Sulfate

    This is a common laboratory test to determine if sulfate anions are present. The sulfate ion can act as a ligand attaching either by one oxygen (monodentate) or by two oxygens as either a chelate or a bridge. [7] An example is the complex Co 2 (SO 4)] + Br − [7] or the neutral metal complex PtSO 4 (PPh 3) 2] where the sulfate ion is acting as ...

  3. Winkler titration - Wikipedia

    en.wikipedia.org/wiki/Winkler_titration

    In the test, an excess of manganese(II) salt, iodide (I −) and hydroxide (OH −) ions are added to a water sample causing a white precipitate of Mn(OH) 2 to form. This precipitate is then oxidized by the oxygen that is present in the water sample into a brown manganese -containing precipitate with manganese in a more highly oxidized state ...

  4. Benedict's reagent - Wikipedia

    en.wikipedia.org/wiki/Benedict's_reagent

    The net reaction between an aldehyde (or an alpha-hydroxy-ketone) and the copper(II) ions in Benedict's solution may be written as: RCHO + 2 Cu 2+ + 5 OH − → RCOO − + Cu 2 O + 3 H 2 O. The hydroxide ions in the equation forms when sodium carbonate dissolves in water. With the citrate included, the reaction becomes:

  5. Ionic strength - Wikipedia

    en.wikipedia.org/wiki/Ionic_strength

    The molar ionic strength, I, of a solution is a function of the concentration of all ions present in that solution. [3]= = where one half is because we are including both cations and anions, c i is the molar concentration of ion i (M, mol/L), z i is the charge number of that ion, and the sum is taken over all ions in the solution.

  6. Fenton's reagent - Wikipedia

    en.wikipedia.org/wiki/Fenton's_reagent

    Fe 3+ is about 100 times less soluble than Fe 2+ in natural water at near-neutral pH, the ferric ion concentration is the limiting factor for the reaction rate. Under high pH conditions, the stability of the H 2 O 2 is also affected, resulting in its self-decomposition. [ 14 ]

  7. Qualitative inorganic analysis - Wikipedia

    en.wikipedia.org/wiki/Qualitative_inorganic_analysis

    This includes ions which form sulfides that are insoluble at high concentrations. The reagents used are H 2 S in the presence of NH 4 OH. NH 4 OH is used to increase the concentration of the sulfide ion, by the common ion effect - hydroxide ions from NH 4 OH combine with H + ions from H 2 S, which shifts the equilibrium in favor of the ionized ...

  8. Sodium sulfate - Wikipedia

    en.wikipedia.org/wiki/Sodium_sulfate

    Sodium sulfate is a typical electrostatically bonded ionic sulfate. The existence of free sulfate ions in solution is indicated by the easy formation of insoluble sulfates when these solutions are treated with Ba 2+ or Pb 2+ salts: Na 2 SO 4 + BaCl 2 → 2 NaCl + BaSO 4. Sodium sulfate is unreactive toward most oxidizing or reducing agents.

  9. Kjeldahl method - Wikipedia

    en.wikipedia.org/wiki/Kjeldahl_method

    Ammonium ion concentration in the acid solution, and thus the amount of nitrogen in the sample, is measured via titration. If boric acid (or some other weak acid) was used, direct acid–base titration is done with a strong acid of known concentration. HCl or H 2 SO 4 can be used.