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Use of Erlenmeyers in Acid Titration
German chemist Emil Erlenmeyer is credited with inventing Erlenmeyer flasks, A.K.A. conical flasks, in 1861. Erlenmeyer flasks have a narrow neck and conical base. Unlike beakers, they are well-suited for swirling and stirring contents during an experiment without spilling and can be stoppered.
 Erlenmeyers are commonly used for titration, a procedure used to determine the concentration of a substance in a solution. For example, winemakers use titration to determine the concentration of acid in wine or must. For better or worse, acid affects the taste of wine. Too much, and the wine tastes sour and sharp. Too little, and it tastes lifeless and flabby.
Acid titration is based on the neutralization reaction between a reactant and an acid reagent of which the volume and concentration is known. In this example, the reactant is the acid in wine, the reagent is sodium hydroxide, and the neutralization reaction is a permanent color change in the wine solution. An indicator is also needed; this substance changes the color of the wine solution as the acid neutralizes.
The winemaker pipets a known value of wine into an Erlenmeyer flask, adds the indicator, and swirls the Erlenmeyer to mix the solution. Using a buret, the winemaker adds sodium hydroxide in carefully controlled amounts. He swirls the solution, adds more reagent, and swirls some more. He adds the sodium hydroxide in increments until there’s just enough to permanently change the color of the wine solution. At this point, the acid is neutralized.
Because the winemaker knows the initial volume of the wine and the concentration and volume of the sodium hydroxide added, he can calculate the concentration of acid in his wine. He can then take steps to increase or decrease the acidity as needed. | 
