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  2. List of purification methods in chemistry - Wikipedia

    en.wikipedia.org/wiki/List_of_purification...

    Pure results of a successful purification process are termed isolate. The following list of chemical purification methods should not be considered exhaustive. Affinity purification purifies proteins by retaining them on a column through their affinity to antibodies, enzymes, or receptors that have been immobilised on the column.

  3. Properties of metals, metalloids and nonmetals - Wikipedia

    en.wikipedia.org/wiki/Properties_of_metals...

    For seven decades, fluorosulfonic acid HSO 3 F and trifluoromethanesulfonic acid CF 3 SO 3 H were the strongest known acids that could be isolated as single compounds. Both are about a thousand times more acidic than pure sulfuric acid. In 2004, a boron compound broke this record by a thousand fold with the synthesis of carborane acid H(CHB 11 ...

  4. Silanol - Wikipedia

    en.wikipedia.org/wiki/Silanol

    Silanols are more acidic than the corresponding alcohols. This trend contrasts with the fact that Si is far less electronegative than carbon (1.90 vs 2.55, respectively). For Et 3 SiOH, the pK a is estimated at 13.6 vs. 19 for tert-butyl alcohol. The pK a of 3−ClC 6 H 4)Si(CH 3) 2 OH is 11. [3]

  5. Solid acid - Wikipedia

    en.wikipedia.org/wiki/Solid_acid

    Crystalline benzoic acid shown here is a solid and an acid, but, in the context of this article, it is not a "solid acid", which are polymeric materials and typically stronger acids. Examples of inorganic solid acids include silico-aluminates ( zeolites , alumina , silico-aluminophosphate), and sulfated zirconia .

  6. Phosphate conversion coating - Wikipedia

    en.wikipedia.org/wiki/Phosphate_conversion_coating

    The bath is a solution of phosphoric acid (H 3 PO 4), containing the desired iron, zinc or manganese cations and other additives. [10] The acid reacts with the iron metal producing hydrogen and iron cations: Fe + 2 H 3 O + → Fe 2+ + H 2 + 2 H 2 O

  7. Acid–base extraction - Wikipedia

    en.wikipedia.org/wiki/Acid–base_extraction

    Acid–base extraction is a subclass of liquid–liquid extractions and involves the separation of chemical species from other acidic or basic compounds. [1] It is typically performed during the work-up step following a chemical synthesis to purify crude compounds [2] and results in the product being largely free of acidic or basic impurities.

  8. Galvanic corrosion - Wikipedia

    en.wikipedia.org/wiki/Galvanic_corrosion

    The paste consists of a lower nobility metal than aluminium or copper. Choose metals that have similar electropotentials. The more closely matched the individual potentials, the smaller the potential difference and hence the smaller the galvanic current. Using the same metal for all construction is the easiest way of matching potentials.

  9. Heavy metal element - Wikipedia

    en.wikipedia.org/wiki/Heavy_metal_(elements)

    The class A and class B terminology is analogous to the "hard acid" and "soft base" terminology sometimes used to refer to the behaviour of metal ions in inorganic systems. [33] The system groups the elements by X m 2 r {\displaystyle X_{m}^{2}r} where X m {\displaystyle X_{m}} is the metal ion electronegativity and r {\displaystyle r} is its ...