bromitymolisininen

Bromothymol blue is a pH indicator that changes color depending on the acidity or alkalinity of a solution. Its chemical formula is C17H18Br2O5S. In acidic solutions, with a pH below 6.0, it appears yellow. As the pH increases and becomes more neutral or alkaline, it transitions through green shades. In alkaline solutions, with a pH above 7.6, it turns blue.

This color change makes bromothymol blue useful in various scientific applications, particularly in titrations and experiments where monitoring pH is important. It is commonly used in biology labs to detect the presence of carbon dioxide, as the production of carbon dioxide in water leads to the formation of carbonic acid, thus lowering the pH and causing the indicator to change from blue to yellow. It is also used in aquariums to test water quality, ensuring a suitable environment for aquatic life.

Bromothymol blue is a weak acid and its color change is due to the deprotonation of its molecule at different pH levels. The compound itself is a solid, typically a white or off-white powder, which is then dissolved in water or alcohol to create a solution for use as an indicator. Its solubility in water is limited, but it is more soluble in alcohol.