EUTECH INSTRUMENTS CADMIUM EPOXY Instruction Manual page 19

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