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Apparently BromPhenol Blue ionization is a two-step process: BH2 BH- + H+ BH- B-2 + H+ (pKa ~ 3.5 - 4.0) The neutral form, whose formula is given in the wikipedia article http://en.wikipedia.org/wiki/Bromphenol_blue , is a strong acid, I haven't seen any estimate of the pKa. The yellow-blue transition which is used as a pH indicator would then be due to the transition from the monoanionic form (yellow) to the dianionic form. The structure of the monoanionic form is given in Scheme 1 of the article: (P.M. Saikia, A. Kalita, B. Gohain, S. Sarma and R.K. Dutta, Colloids Surf. A 216 (2003), p. 21.). Its formation appears to involve ionization of one phenolic OH followed by enol-keto transition with double-bond formation to the central carbon, displacing the sulfonic adduct to that atom. The dianionic form is presumably the same, but with the remaining phenolic OH ionized.
What else can I help you with?
What is the colour of bromophenol blue when neutral?
Bromophenol blue is green when neutral.
Does Amax of bromophenol blue vary with concentration?
Yes, the absorbance maximum (Amax) of bromophenol blue does vary with concentration. As the concentration of bromophenol blue increases, the Amax shifts from its initial value. This change in Amax can be used to determine the concentration of bromophenol blue in a solution through spectrophotometric analysis.
Which is more polar bromophenol blue or phenolphthalein?
Phenolphthalein is more polar than bromophenol blue due to its structure and functional groups. Phenolphthalein contains more oxygen atoms that can participate in hydrogen bonding, making it a more polar compound compared to bromophenol blue.
What happens if you mix bromphenol blue and NaOH?
When bromophenol blue is mixed with NaOH, the solution turns blue because the pH becomes alkaline. Bromophenol blue is a pH indicator that changes color in different pH ranges. In the presence of NaOH, which is a base, the bromophenol blue changes from yellow (at acidic pH) to blue (at alkaline pH).
Can you use bromophenol blue in place of bromothymol blue?
No, bromophenol blue and bromothymol blue are not interchangeable. They have different pH ranges for color changes and may not give accurate results if substituted for each other in experiments or procedures.
What is the colour of bromophenol blue when neutral?
Bromophenol blue is green when neutral.
Does Amax of bromophenol blue vary with concentration?
Yes, the absorbance maximum (Amax) of bromophenol blue does vary with concentration. As the concentration of bromophenol blue increases, the Amax shifts from its initial value. This change in Amax can be used to determine the concentration of bromophenol blue in a solution through spectrophotometric analysis.
What does dye contain?
The loading dye comprises bromophenol blue, Ficoll 400 and water majorly while Xylene cyanol, Tris and EDTA are optional in it. Bromophenol blue is one of the most popular indicators of DNA in agarose gel electrophoresis. Bromophenol blue is a pH indicator.
Which is more polar bromophenol blue or phenolphthalein?
Phenolphthalein is more polar than bromophenol blue due to its structure and functional groups. Phenolphthalein contains more oxygen atoms that can participate in hydrogen bonding, making it a more polar compound compared to bromophenol blue.
What is the chemical formula of Alcian blue?
The chemical formula of Alcian blue is C56H68N16O20S6Na4.
What is the pka of bromophenol blue?
Phenols are acidic substances (pH over 7).
What happens if you mix bromphenol blue and NaOH?
When bromophenol blue is mixed with NaOH, the solution turns blue because the pH becomes alkaline. Bromophenol blue is a pH indicator that changes color in different pH ranges. In the presence of NaOH, which is a base, the bromophenol blue changes from yellow (at acidic pH) to blue (at alkaline pH).
Can you use bromothymol blue in place of bromophenol blue?
no.heres why:bromophenol-blue-1bromothymol-blue-1
What is the chemical formula for blue 1?
The chemical formula for Blue 1, also known as Brilliant Blue FCF, is C37H34N2Na2O9S3.
Can you use bromophenol blue in place of bromothymol blue?
No, bromophenol blue and bromothymol blue are not interchangeable. They have different pH ranges for color changes and may not give accurate results if substituted for each other in experiments or procedures.
If you add a bromophenol blue solution to .01M HCl what solution color would result after mixing?
The bromophenol blue will turn yellow in the presence of an acidic solution like 0.01M HCl.
Why Phenapthalein and Bromophenol blue are used as indicators?
Phenolphthalein and bromophenol blue are used as indicators due to their distinct color changes at specific pH ranges, making them useful for determining acidity or alkalinity in various solutions. Phenolphthalein transitions from colorless to pink as the pH increases from around 8.2 to 10, while bromophenol blue shifts from yellow to blue between pH 6.0 and 7.6. These properties allow them to effectively signal the endpoint in titrations and other chemical analyses. Their clear visual indicators facilitate easy interpretation of results in laboratory settings.
