Question

Compare the structure of xylenol orange to phenolphthalein. Do some research to determine why phenolphthalein changes color under acidic or basic conditions. Based on the chemistry of phenolphthalein, explain why xylenol orange is a different color in the presence and absence of zinc ions. It is useful to note that the xylenol orange-zinc complex that is red must absorb light around 500-550 nm while the free xylenol orange molecule is yellow, so must absorb light around 400-450 nm.

Answer 1

pentamethoxytriphenylmethanol, phenanthroline, phenazine, phenol red, phenolphthalein, phenolphthalein diphosphate, phenothiazine, phenylazoaniline, phenylazodiphenylamine, phenylazoformic acid, phenylazophenol, phloxine B, phthalocynine, pinacyanol chloride, plasmocorinth, ponceau S, primuline, procion red MX-5B, procion yellow H-E3G, prussian blue, purpurin, pyridlazo naphthol, pyridylazoresorcinol sodium salt, pyrocatechol violet, pyrogallol red, pyronin B, quinaldine red, quinizarin, quinoline yellow, reactive black 5, reactive blue 15, reactive blue 2, reactive blue 4, reactive orange 16, resazurin, resorcin crystal violet, rhodamine B, rhodamine B base, rhodamine GG, rhodamine S, rhodanine, rosalic acid, rose bengal, rose bengal iactone, safranine O, solvent blue 35, solvent blue 59, solvent green 3, styryl 7, sudan black B, sudan orange G, sudan red 7B, sulfobromophthalein sodium salt, sulforhodamine B, tartrazine, tetrabromophenol blue, tetrabromo phenolphthalein, tetrabromo phenolphthalein, tetraiodo phenolphthalein, tetraphenyl-butadiene, tetrazolium violet, thiazol yellow G, thioflavin S, thioflavin T, thionin, thymol blue, thymolphthalein, thymolphthalein monophosphate, thymolphthalein monophosphate, toluidine blue O, triphenylmethyl bromide, tropaelin O, trypan blue, turmeric, vanillin azine, variamine blue RT salt, variamine blue RT salt, victoria blue B, victoria blue B, victoria pure blue BO, wright stain, xilidine ponceau 2R„ xylenol blue, and xylenol orange [00113] Some of these dyes are fluorescence dyes and some of them changed their fluorescence upon irradiation. [00114] The term "converter(s)" is used for any material, substance or mixture, which can be complexed or doped with other substances, which when irradiated with high energy radiations, both ionizing and nonionizing, produces relatively lower energy radiation, either of the same or different type, via any process including scattering, attenuation, fluorescence, phosphorescence, and conversion. Inorganic and organometallic compounds are preferred as converters because they have the ability to transfer/convert high-energy radiation into lower energy radiation via many processes, such as scattering, absorbance, fluorescence, and phosphorescence. The selection of a converter depends upon the type of radiation to be monitored and its energy. For example, lead and barium salts are good converters for monitoring X-ray radiation and boron, lithium salts are good converters for measuring thermal neutrons.