Elemental magnesium ... unlike the other alkali metals Unbelievable!
Osmosis The osmotic pressure is defined to be the minimum pressure required to maintain an equilibrium minimum!
18-Crown-6 ... wraps around metal cations, providing an octahedral cavity. It is 6-coordinate, not octahedral.
Niacin pka=4.85. This pK refers to the protonation of the N atom. The carboylic acid part of the molecule has a pKa of ca. 2. This is a howler because only a single value was cited.
Helium ...it exists only as a gas except in extremely cold conditions. Meaningless! Phrase removed.
Saponification The alkoxide is more basic than the conjugate base of the carboxylic acid, and hence proton transfer is rapid. :An example of confusion between an equilibrium property, basicity, and a kinetic property, reaction rate.
Chlorite dismutase ..the two substrates of this enzyme are chloride ion and oxygen, whereas its product is chlorite. It's the other way round - oxygen is a product. This error is present in the enzyme catalogue (EC220.127.116.11), from which, presumably, it was copied.
Nitrogenase Dinitrogen is quite inert because of the strength of its N≡N triple bond. What is astonishing about this error is that it is followed by a correct statement relating inertness to high activation energy.
Glucose Like all hexoses, glucose has the molecular formula C6H12O6. It has fifteen stereoisomers. Glucose has 15 isomers? What nonsense!
Sulfur trioxide#Structure and bonding (Version 14 Aug. 2014) As sulfur trioxide is centrosymmetric , it has no electrical dipole.The molecule cannot have a centre of symmetry, as it has 3-fold symmetry
Metal ions in aqueous solution version 24 Sept.2013. Raman spectroscopy is particularly useful because the excitation wavelength for the Raman spectra could be choosen in the region of water's transparancy. Nonsense! It's nothing to do with excitation wavenength. Reverted
Radioactive tracer Tritium and carbon-14-labeled water and glucose are commonly used.. Revised
Fractional crystallization (chemistry) [In] fractional crystallization [of] two or more substances they will crystallize out of solution (precipitate) at different rates. It is not a matter of rates, but of different solubility products which determine the equilubrium state.
polyphosphate: .. are anionic phosphate polymers linked between hydroxyl groups and hydrogen atoms. Article extensively revised
EDTA is an amino acid. Replaced by polyamino carboxylate.
Crystal field excitation dd-transitions on a copper atom that is surrounded by a hexagon of oxygen atoms. Changed in Revision as of 19:38, 17 May 2010 to an octahedra. Finally changed to an octahedron.
Recrystallization (chemistry) Since "Compound A" is in excess this will usually result in these crystals forming first see fractional crystallization, above
Molecular vibration (version 19 December 2010) The three atomic molecule have three modes of vibration irrespective of whether these are linear or nonlinear. Confuses normal modes of vibration with vibration frequencies.
Hydroxide (version 5 December 2010) When hydroxide ion is mixed with hydrogen gas, water forms. Article re-written.
Zwitterion (Version 27 Dec. 2010) Most amino acids at physiological pH are zwitterionic. Confusion between biological pH and isoelectric point.
Technetium-99m(Earlier version):The molybdenum-99 is in the form of sodium molybdate in ion resins. When the Mo-99 decays to Tc-99m this does not form a similar compound Corrected by another editor.
Borate the fictitious ions [ .. H2BO−
3 and BO3−
3] are easier to use for pKa values and other calculations. Article revised.
Uranate Uranate is the chemical term for oxideanions of the element uranium. Examples of uranates include UO22-, UO32−, and UO42− Article re-written.
pH "The meaning of the "p" in "pH" is unknown". No it isn't. It means decimal cologarithm
pH "where aH+ is the activity of hydrogen ions in units of mol/L (molar concentration)" Logarithms can only be taken of numbers, so the idea of taking a logaritm of a concentration is nonsense. In fact activity is dimensionless.
Electromagnetic absorption by water Rotational transitions don't affect significantly the absorption spectrum of water. Complete omission of vibration-rotation effects. Article re-wrtten
Buffer solution (Revision as of 08:43, 6 May 2013) most of the added hydroxide ion is consumed in the reaction OH- + HA → H2O + A- ... which results in a decrease in pH. Corrected by user:Edgar181
Bond dissociation energy There seem to be conflicting definitions. One at zero Kelvin, which presumably is derived from quantum chemical calculations, and the other obtained from experimental data. The experimental one depends on the conditions used for the measurements.
Thank you for your extensive contribution to Wikipedia articles on chemistry. Stan J. Klimas (talk) 14:46, 7 December 2008 (UTC)
The Chemistry Star
It is good to have you around! Qualitity articles pave your way. Stone (talk) 23:11, 11 March 2009 (UTC)
The Resilient Barnstar
Hi Petergans! I'm glad you learnt to add the references. Unfortunately, it lacks third-party sources. Otherwise, its notability will be challenged. Thanks for your attention. All the best, Kayau (Talk to me!See what I've done!Sign my guestbook!) 05:04, 4 July 2009 (UTC)