what is the purpose of the bromophenol blue dye in the samples
as a pH indicator a dye a color marker a pH indicator
title: Bromothymol blue text: Bromothymol blue Bromothymol blue (also known as bromothymol sulfone phthalein and BTB) is a pH indicator. It is mostly used in applications that require measuring substances that would have a relatively neutral pH (near 7). A common use is for measuring the presence of carbonic acid in a liquid. It is typically sold in solid form as the sodium salt of the acid indicator. Bromothymol blue acts as a weak acid in solution. It can thus be in protonated or deprotonated form, appearing yellow or blue, respectively. It is bright aquamarine by itself, and greenish-blue in a neutral solution. The title: Bromothymol blue text: it is already blue, and a few drops are used on a water slide. The cover slip is placed on top of the water droplet and the specimen in it, with the blue coloring mixed in. It is sometimes used to define cell walls or nuclei under the microscope. Bromothymol is used in obstetrics for detecting premature rupture of membranes. Amniotic fluid typically has a pH > 7.2, bromothymol will therefore turn blue when brought in contact with fluid leaking from the amnion. As vaginal pH normally is acidic, the blue color indicates the presence of amniotic fluid. The test title: Bromothymol blue text: presence of one moderate electron withdrawing group (bromine atom) and two moderate donating groups (alkyl substituents) are responsible for bromothymol blue's active indication range from a pH of 6.0 to 7.6. While the conjugation is responsible for the length and nature of the color change range, these substituent groups are ultimately responsible for the indicator's active range. Bromothymol blue is sparingly soluble in oil, but soluble in water, ether, and aqueous solutions of alkalis. It is less soluble in nonpolar solvents such as benzene, toluene, and xylene, and practically insoluble in petroleum ether. To prepare a solution for use as title: Bromine test text: Bromine test In organic chemistry, the bromine test is a qualitative test for the presence of unsaturation (carbon-to-carbon double or triple bonds) and phenols. An unknown sample is treated with a small amount of elemental bromine in an organic solvent, being as dichloromethane or carbon tetrachloride. Presence of unsaturation and/or phenol in the sample is shown by disappearance of the deep brown coloration of bromine when it has reacted with the unknown sample. The formation of a brominated phenol in form of a white precipitate indicates that the unknown was a phenol. The more unsaturated an unknown is, the more title: Organobromine compound text: contain also bromine moieties. Like other halogenated pesticides, bromoxynil is subject to reductive dehalogenation under anaerobic conditions, and can be debrominated by organisms originally isolated for their ability to reductively dechlorinate phenolic compounds. Many dyes contain carbon-bromine bonds. The naturally occurring Tyrian purple (6,6’-dibromoindigo) was a valued dye before the development of the synthetic dye industry in the late 19th century. Several brominated anthroquinone derivatives are used commercially. Bromothymol blue is a popular indicator in analytical chemistry. Commercially available organobromine pharmaceuticals include the vasodilator nicergoline, the sedative brotizolam, the anticancer agent pipobroman, and the antiseptic merbromin. Otherwise, organobromine compounds are