Thermo Fisher Scientific Ion Selective Electrodes Cadmium - Manual (Page 19)

Instruction Manual Cadmium Electrode
19
incorrect reference use recommended
filling solution filling solution
Low Slope or
standards contaminated prepare fresh
No Slope or incorrectly made standards
ISA not used use recommended ISA
standard used as ISA use ISA
electrode exposed check section
to complexing agents entitled
Precipitation
and Complexation
air bubble on remove bubble by
membrane redipping probe
"Incorrect Answer"
incorrect scaling plot millivolts on
(but calibration of semi-log paper the linear axis. On
curve is good) the log axis, be sure
concentration numbers
within each decade are
increasing with
increasing concentration.
incorrect sign be sure to note sign of
millivolt number correctly
incorrect standards prepare fresh standards
wrong units used apply correct
conversion factor:
10
-3
M = 112 ppm as Cd
+2
complexing agents check section entitled
in sample
Precipitation and
Complexation;
use titration