Bromothymol blue
From Biocrawler, the free encyclopedia.
| Bromothymol blue (pH indicator) | ||
| below pH 6.0 | above pH 7.6 | |
| yellow | ↔ | blue |
| edit this box (http://www.biocrawler.com/w/index.php?title=Template:PH_indicator_template&action=edit) | ||
Bromothymol blue, also known as bromthymol blue, is a chemical indicator for weak acids and bases.
The bromothymol blue acts as a weak acid in solution and therefore can be in acid or base forms which appear yellow and blue respectively. Typically solid bromothymol blue is sold as a sodium salt of the acid indicator.
C27H28Br2O5S ↔ H+ + C27H27Br2O5S-
The pKa for bromothymol blue is 7.1.
Formula: C21H15NaBr2O3S
Alternative name: Dibromothymolsulfonephthalein, BTB
