Thermo Fisher Scientific Ion Selective Electrodes Copper - Manual (Page 12)

Instruction Manual Copper Electrode
12
1 A 0.1 1.0X10 -3 1.0X10 -8
2 A 0.1 2.0X10 -3 2.0X10 -8
3 A 0.2 4.0X10
-3
4.0X10
-8
4 A 0.2 6.0X10
-3
6.0X10
-8
5 A 0.4 1.0X10 -2 9.9X10 -8
6 B 2.0 2.9X10 -2 2.9X10 -7
7 B 2.0 4.8X10
-2
4.8X10
-7
Pipette A = 1 ml graduated pipette
Pipette B = 2 ml pipette
Solutions: additions of 1 ppm or 1.0X10
-5
M standard to 100 ml
of solution prepared in Step 3 above.
7. On semi-logarithmic graph paper, plot the mV reading
(linear axis) against the concentration (log axis) as
in Figure 1.
8. Rinse the electrode(s) and blot dry.
9. Measure out 100 ml of the sample into a 150 ml beaker.
Add 1 ml of low level ISA. Place the beaker on the
magnetic stirrer and begin stirring at a constant rate.
Lower the electrode tip(s) into the solution. After
the reading has stabilized, record the mV reading and
determine the concentration from the low level
calibration curve.
10. Prepare a new low level calibration curve daily.
Check the calibration curve every two hours by
repeating Steps 3-7 above.
Low Level Cupric Determination (using an ion meter)
1. Using 20 ml of standard ISA, dilute to 100 ml with
distilled water. This low level ISA (1.0M NaNO
3
) is
added at the rate of 1 ml low level ISA to each 100 ml
of solution. The background ionic strength will be
1.0X10
-2 M.
2. Follow the steps given in Direct Measurement of Cupric
Ion (using an ion meter) to the end of Step 7.
3. Add 100 ml of distilled water and 1 ml of low level ISA
to a 150 ml beaker. Place the beaker on the magnetic
stirrer and begin stirring at a constant rate.