Thermo Fisher Scientific CyberScan pH 5000 - Manual (Page 122)

Instruction Manual CyberScan pH5500/ 5000
11.5 Analate addition
The analate addition method is useful when your sample is at an
elevated temperature and you want to negate the effect that
temperature will have on the concentration calculation. This method
is also useful if you have only a small amount of sample available.
The analate addition method differs only slightly from the known
addition method. The difference being the solution that you are taking
your initial mV reading in is actually the standard before and after the
sample is added is used to calculate the concentration of the ion of
interest, with the analate addition method, both the sample and the
standard solution contain the ionic species of interest. See ISE theory
page 133.
To take a measurement
1. Immerse the ion selective electrode in a known volume of the
sample solution.
2. Stir the sample.
3. Touch AA to take the first mV reading of sample. Wait for the
reading to stabilize (STABLE will appear).
OR
Touch AA to accept the current reading.
4. Add a known volume of standard solution to the sample.
5. Touch AA to take the second mV reading of sample. Wait for the
reading to stabilize (STABLE will appear).
OR
Touch AA to accept the current reading.
6. Use the keypad to enter the sample volume.
7. Touch enter to accept the value.
8. Use the keypad to enter the standard volume.
9. Touch enter to accept the value.
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