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Testing Samples for Total Hardness
6200018bench.fm
Section 5
5.3 Testing Samples for Total Hardness
Refer to
Table 9
to choose between using a buret or a digital titrator,
depending on the sample concentration.
Use the information in
Table 10
to determine the correct sample volume and
pipet size for the digital titrator procedure.
Use the information in
Table 11
to determine the correct sample volume and
pipet size for the buret titration procedure.
9.
Repeat steps 1-8 twice. 10. Use the average
value for the titer of
Reagent 3.
Repeat
steps 1-8 twice.
Average the three
values for the titer
of Reagent 3
Table 9 Choosing a Titration Method
Sample Concentration
(mg/L as CaCO
3
)
Titration Method
10 – 100
Digital Titrator
100 – 1000
Buret
Table 10 Required Sample Volume for Digital Titrator Procedure
Sample Concentration
(mg/L as CaCO
3
)
Sample Volume (mL)
10 – 50
20
50 – 100
10
Table 11 Required Sample Volume for Buret Titration Procedure
Sample Concentration
(mg/L as CaCO
3
)
Sample Volume (mL)
100 – 250
100
250 – 500
50
500 – 1000
20
