Is to determine the amount of a chemical species.
how to make dosage?
hydrochloric acid assayed by a sodium hydroxide solution
It is necessary to determine the concentration of the hydrochloric acid
we will take a precise volume of solution (H+Cl-)
to detect equivalence poured bromothymol blue.
Evolution of pH during dosage
It is noted that the color is yellow at the start so that there is no acid,
then poured soda thus increasing pH (because disappearance of H + ions),
the solution turns blue, therefore the pH thereof is neutral,
it is called equivalence.