Bromocresol Blue vs Bromocresol Purple
There are several compounds that are used to check the acidity or basicity levels of solutions. All solutions have a pH value from 0 to 14 that is known as their pH value. Solutions with a pH values less than 7 are considered acidic while those having a pH value more than 7 are called basic. A solution with pH value 7 is called neutral. The compounds that are used to check the pH values of solutions are called pH indicators. Bromocresol Blue and Bromocresol Purple are two very good pH indicators used in biology and analytical chemistry. Though they perform the same basic function, there are differences between Bromocresol Blue and Bromocresol Purple that will be discussed in this article.
It is a very good pH indicator that is used for educational purposes only. It is not considered hazardous as it is not reactive and poses no health problems. It is a sodium salt. If it goes into eyes accidentally, one must wash eyes with excess water for 15 minutes lifting upper and lower eyelid frequently. If someone consumes the compound, poison control has to be called immediately. When inhaled, fresh air will bring back normal breathing. It is a non flammable solid that emits acrid fumes when heated to decomposition. Bromocresol purple must be stored with proper ventilation.
It is a greenish violet powder with no odor. It is a non flammable solid and if someone consumes it, he must be given 1-2 cups of milk to induce vomiting. When heated to decompose, gives out acrid fumes. It is not hazardous but must be used with caution. If Bromocresol blue goes inside eye, the person must wash eyes under water for some time to wash it away. It is an indicator used in acid base titrations where a weak base is titrated against a weak acid. The indicator is yellow at pH less than 6 and blue at pH more than 7.6. It turns green at pH 7 which is the neutralization pH of a weak acid/base solution.