Search results
Results from the WOW.Com Content Network
The conversion between hydroxyl value and other hydroxyl content measurements is obtained by multiplying the hydroxyl value by the factor 17/560. [2] The chemical substance may be a fat, oil, natural or synthetic ester, or other polyol. [3] ASTM D 1957 [4] and ASTM E222-10 [5] describe several versions of this method of determining hydroxyl value.
In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula −OH and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry , alcohols and carboxylic acids contain one or more hydroxy groups.
A base in chemistry is a substance that can accept hydrogen ions or donate a pair of valence electrons to form a bond.
From this point, two routes are available. Treatment of the product with acetone in the presence of an acid catalyst converts four of the remaining hydroxyl groups to acetals. The unprotected hydroxyl group is oxidized to the carboxylic acid by reaction with the catalytic oxidant TEMPO (regenerated by sodium hypochlorite – bleaching solution
Animation of a strong acid–strong base neutralization titration (using phenolphthalein).The equivalence point is marked in red. In chemistry, neutralization or neutralisation (see spelling differences) is a chemical reaction in which acid and a base react with an equivalent quantity of each other.
China Medical University (Taiwan)'s Laboratory A wet lab is a type of laboratory in which a wide range of experiments are performed, for example, characterizing of enzymes in biology, titration in chemistry, diffraction of light in physics, etc. - all of which may sometimes involve dealing with hazardous substances. [2]
The hydroxyl radical can damage virtually all types of macromolecules: carbohydrates, nucleic acids , lipids (lipid peroxidation) and amino acids (e.g. conversion of Phe to m-Tyrosine and o-Tyrosine). The hydroxyl radical has a very short in vivo half-life of approximately 10 −9 seconds and a high reactivity. [5]
It is now primarily used as a teaching tool, having been replaced in the laboratory by other chromatography methods such as thin-layer chromatography (TLC). This analytic method has three components, a mobile phase, stationary phase and a support medium. The mobile phase is a solution that travels up the stationary phase by capillary action ...