Taylor Drop Test Kit, Alkalinity (Caustic Soda), Phenolphthalein, 1 drop = 0.1 or 1% NaOH

Alkalinity is the acid-neutralizing capacity of water. Although many bases (such as borates, phosphates, and silicates) contribute to a water’s alkalinity, it is primarily a function of the carbonate, bicarbonate, and hydroxide concentrations. Alkalinity control is important in many processes including municipal water and wastewater treatment, paper and textile manufacturing, commercial laundering, warewashing, beverage production, and boiler and cooling system operation.

Alkalinity is determined by titration with a standard acid to a designated pH and recorded as either P, M, or T alkalinity. P alkalinity is titrated to an endpoint pH of 8.3 using phenolphthalein as the indicator, M alkalinity is titrated to an endpoint pH of 4.6 using methyl orange as the indicator, and T alkalinity is titrated to an endpoint pH of 4.5 using a blended indicator (bromocresol green/methyl red). If sulfuric acid is being added to modify pH, it will also alter the P/T alkalinity relationship.