You will be given a definition of a task first, then some input of the task.
In this task, you are given a sentence in the Spanish language. Your task is to translate the Spanish sentence into the English language.

En la determinación de la dureza del agua debida a la presencia de iones Ca2+ y Mg2+ se utiliza como reactivo valorante
Output:
In the determination of water hardness due to the presence of Ca2 + and Mg2 + ions, the titrant reagent is used