Hanna Instruments HI931, Руководство пользователя, Страница: 211 / 218

17
TITRA
TION THEORY
By Volume
C titrant Concentration of titrant (N)
V standard Volume of Standard (mL)
C standard Concentration of standard (eq/L)
V titrant Volume of Titrant (L)
5.3. BLANK TITRATION
In a blank titration a pre-titration is performed, often times on the solvent to be used for the sample titration, and the titrant volume
required to reach the endpoint is noted. This blank value nullifies error due to titrant required to react with the components of the
titration solution matrix. The basic titration equation can be used for a blank titration, with the single modification that the volume
of titrant used in the blank titration should be subtracted from the regular titration titrant volume.
C Sample Sample Concentration (g/100g)
C titrant Titrant Concentration (eq/L)
V sample Volume of Titrant required for the sample (L)
V blank Volume of Titrant required for the blank (L)
Ratio Equivalence ratio of analyte/ titrant (mol analyte/ eq titrant)
FW analyte Formula Weight of the Analyte (g/mol)
m sample Mass of sample (g)
5.4. MULTIPLE ENDPOINT TITRATION
Some titrations have two or more endpoints, each corresponding to the equivalence point for a specific reaction. Multiple endpoint
titrations are similar to a blank titration in that the volume of titrant required to reach the first endpoint is subtracted from the titrant
volume used to reach the next sequential endpoint.
C sample1 Sample 1 Concentration (g/100g)
C sample2 Sample 2 Concentration (g/100g)
C sample3 Sample 3 Concentration (g/100g)
V titrant 1 Volume of titrant required to reach the first end point (L)
V titrant 2 Volume of titrant required to reach the second end point (L)
V titrant 3 Volume of titrant required to reach the third end point (L)
C titrant Concentration of titrant (N)