Derived from the laboratory burette method (titration method), the Lovibond drop test range is an established methodology used across the water industry forming an integral part of the analytical program of many a speciality chemical supplier.
|In the drop test method like in the laboratory titration technique, a solution of known concentration is used to determine the concentration of an unknown solution. Instead of using a burette to regulate the amount of solution added a dropper bottle is used. Like in the standard laboratory burette method, a known solution (the titrant) is added from a dropper to a known quantity of the unknown solution (the analyte) until a colour change indicates the reaction is complete (image opposite). The following calculation is used to determine the concentration of the analyte (sample).|
Total Analyte in mg/l = Number of Drops X Factor (based on sample size, in mls, and the factor obtained from a table provided, an example is shown below).
Lovibond’s selection of reagents gives results fast, making this adaption of titration, the drop test, a quick, easy and reliable option for testing water samples in the field.
Caution needs to be given for the presence of other compounds that may interfere with the endpoint analysis. Each test method will indicate any potential compounds which will increase the observed result and therefore, provide false concentration readings.
- Accuracy to ± 10%