EXP 20

• Vinegar is a dilute solution of acetic acid.
• Since vinegar is an acid it can be titrated directly with a standard solution of a base (or alkali).
• acetic acid content of some commercially prepared vinegars will be determined using a type of volumetric analysis called Acidimetry.
• by titrating the unknown concentration of acetic acid present in vinegar solutions with a strong base; Sodium hydroxide (NaOH).
• The endpoint of the titration will be detected using a Phenolphthalein indicator
• Phenolphthalein indicator; an acid-base indicator that changes color from clear to a faint pink in going from its acidic form to its basic form.
• The percent acidity is the bases for determining the legality of commercial vinegars.
• Vinegar is regulated by the Food and Drug Administration (FDA)
• the acetic acid content of a vinegar will vary from about 5.0 – 8.0% for Table Vinegars
• 18.0% for Pickling Vinegars.
• pure acetic acid is referred to as “Glacial Acetic Acid”