Horiba Scientific 6560S-10C Instruction Manual page 33

It is best to control the stirring speed so that the stir bar will
rotate 3 or 4 turns per second.
If swirling occurs on the surface, the stirring speed is too
fast. Reduce the speed to a level where swirling does not
Note Note
occur.
Additive amount of ISA
(
In the case using different volume from the example, note
Note Note that the volume ratio shall be the standard solution: the ISA
= 50:1.
4
Prepare the second solution for calibration.
(1) Put 50 mL of 1000 mg/L standard solution into a 100 mL beaker.
(2) Add 1 mL of ISA.
(3) Stir the solution slowly with a magnetic stirrer.
(1) Standard solution (1000 mg/L)
"About activity" (page 60))
50 mL
(2) ISA
1 mL
Beaker: 100 mL
(3)
Stir the solution slowly
with a magnetic stirrer.
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