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Phenolphthalein is slightly soluble in water and usually is dissolved in alcohols in experiments. It is a weak acid, which can lose H + ions in solution. The nonionized phenolphthalein molecule is colorless and the double deprotonated phenolphthalein ion is fuchsia. Further proton loss in higher pH occurs slowly and leads to a colorless form.
In 1871 he discovered the synthesis of phenolphthalein by condensation of phthalic anhydride with two equivalents of phenol under acidic conditions (hence the name). That same year he was the first to obtain synthetic fluorescein , a fluorophore pigment which is similar to naturally occurring pyoverdin that is synthesised by microorganisms (e.g ...
Phenolphthalein can be synthesized by the condensation of phthalic anhydride with two equivalents of phenol under acidic conditions (hence the name). It was discovered in 1871 by Adolf von Baeyer. [8] [9] [10] Synthesis of phenolphthalein [11]
Upon reduction, the very intense pink color of the cationic form of phenolphthalein fades to a faint yellow color. It is this form of phenolphthalein that is present in Kastle–Meyer test kits. In order to generate the intense pink color indicative of a positive test, the reduced phenolphthalein must be oxidized back to its normal, colored form.
Solution: The main components of a universal indicator, in the form of a solution, are thymol blue, methyl red, bromothymol blue, and phenolphthalein. This mixture is important because each component loses or gains protons depending upon the acidity or alkalinity of the solution being tested. It is beneficial to use this type of universal ...
Michael Sendivogius (/ ˌ s ɛ n d ɪ ˈ v oʊ dʒ i ə s /; Polish: Michał Sędziwój; 2 February 1566 – 1636) was a Polish alchemist, philosopher, and medical doctor.A pioneer of chemistry, he developed ways of purification and creation of various acids, metals and other chemical compounds.
For optimal accuracy, the color difference between the two species should be as clear as possible, and the narrower the pH range of the color change the better. In some indicators, such as phenolphthalein, one of the species is colorless, whereas in other indicators, such as methyl red, both species confer a color. While pH indicators work ...
Space-filling model of the H 2 O molecule.. In chemistry, the history of molecular theory traces the origins of the concept or idea of the existence of strong chemical bonds between two or more atoms.