Chemistry:Chlorophenol red

From HandWiki
Chlorophenol red
Skeletal formula of chlorophenol red in cyclic form
Ball-and-stick model of the chlorophenol red molecule in cyclic form
Names
Preferred IUPAC name
3,3-Bis(3-chloro-4-hydroxyphenyl)-2,1λ6-benzoxathiole-1,1(3H)-dione
Other names
3′,3′-Dichlorophenolsulfonaphthalein
Identifiers
3D model (JSmol)
ChemSpider
EC Number
  • 224-619-2
UNII
Properties
C19H12Cl2O5S
Molar mass 423.26 g·mol−1
Melting point 261 °C (502 °F; 534 K)[1]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)
Infobox references
Tracking categories (test):
Chlorophenol red (pH indicator)
below pH 5.4 above pH 6.8
5.4 ⇌ 6.8

Chlorophenol red is an indicator dye that changes color from yellow to violet in the pH range 5.4 to 6.8.[2] The pH of a substance is determined by taking the negative logarithm of the Hydronium ion concentration and the indictor changes color due to the dissociation of H+ ions.[3] The lambda max is at 572 nm.[4]

Properties and uses

The dissociation mechanism of chlorophenol red is similar to that of phenolphthalein meaning it can be used as a color indicator. The dissociation of hydroxyl and hydrogen atoms creates the dissociate scheme of chlorophenol red to change color from yellow to red.[5] The pH properties of chlorophenol red are used to selectively determine the amount of chlorine dioxide in drinking water. Chlorophenol red selectively reacts with 0.1–1.9 mg/L chlorine dioxide at pH 7.[6] The electrochemical properties of Chlorophenol red allows it to be a chromogenic label and can undergo oxidation creating several phenolic intermediates. The bacterial hydrolysis of a chlorophenol red labelled substrate produces chlorine retaining intermediates on electrodes.[7]

References

  1. ↑ Haynes, p. 3.116
  2. ↑ Haynes, p. 8.88
  3. ↑ "pH Indicators" (in en). 2013-10-02. https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Acids_and_Bases/Acid_and_Base_Indicators/PH_Indicators. 
  4. ↑ "Chlorophenol Red". https://www.sigmaaldrich.com/catalog/product/aldrich/199524. 
  5. ↑ Hanai, Toshihiko (2016). "Quantitative Evaluation of Dissociation Mechanisms in Phenolphthalein and the Related Compounds.". Journal of Computer Chemistry 15: 13–21. doi:10.2477/jccj.2015-0055. https://www.researchgate.net/publication/301942181. 
  6. ↑ Sweetin, Deborah L.; Sullivan, Elizabeth; Gordon, Gilbert (1996-01-01). "The use of chlorophenol red for the selective determination of chlorine dioxide in drinking water". Talanta 43 (1): 103–108. doi:10.1016/0039-9140(95)01721-6. PMID 18966469. 
  7. ↑ Casimero, Charnete; Bigham, Teri; McGlynn, Ruairi J.; Dooley, James S. G.; Ternan, Nigel G.; Snelling, William J.; Critchley, Megan E.; Zinkel, Cameron L. et al. (2019-12-01). "Electroanalytical properties of chlorophenol red at disposable carbon electrodes: Implications for Escherichia coli detection". Bioelectrochemistry 130: 107321. doi:10.1016/j.bioelechem.2019.06.006. PMID 31306878. https://clok.uclan.ac.uk/29045/1/29045%201-s2.0-S1567539419303445-main.pdf. 

Cited sources