Hach DR/700 Procedures Manual page 222

SODIUM CHROMATE,
7.
Place the blank in
the cell holder.
Note: Typical indoor
lighting permits the
DR/700 to operate with
the cell compartment
cover open. In bright
sunlight, it may be
necessary to close the
cell compartment cover.
Transfer 10-mL of the
blank solution to a
10-mL cell. If the 10-mL
cell is used for the blank,
another 10-mL cell must
be used for the sample.
10.
Press:
READ
The display will
count down to 0.
Then the display will
show the results in
mg/L sodium
chromate (Na CrO
2
Note: See table below to
convert sodium
chromate to other units.
8.
Press:
ZERO
The display will
count down to 0.
Then the display will
show 0.00 mg/L and
the zero prompt will
turn off.
Table 1. Conversion Factors
To convert reading from
mg/L Na
mg/L Na
).
4
45-50
continued
9.
Place the prepared
sample in the cell
holder.
Note: Typical indoor
lighting permits the
DR/700 to operate with
the cell compartment
cover open. In bright
sunlight, it may be
necessary to close the
cell compartment cover.
Transfer 10-mL of the
blank solution to a
10-mL cell. If the 10-mL
cell is used for the blank,
another 10-mL cell must
be used for the sample.
To
CrO CrO 2-
2 4 4
CrO Cr 6+
2 4
Multiply by
0.72
0.321