Hanna Instruments HI83300 Instruction Manual page 186

• Press Continue and the display will show the countdown, or alternatively, wait for 2 minutes.
During this period, the chloroform layer separates from the aqueous layer.
• Remove the cap.
• Insert a clean plastic pipette below the upper aqueous layer to transfer
the lower chloroform layer into a cuvette. Do not transfer any of the upper
aqueous layer.
Notes: The solution in the cuvette must be clear. If the solution is cloudy, the separation
between the chloroform and aqueous layer can be improved by gently warming the cuvette
(holding the vial in your hand). If the chloroform layer contains some aqueous drops
hanging on the cuvette wall, gently swirl or invert the cuvette.
It is important to transfer at least 7 mL of chloroform layer into the measurement cuvette,
thus up to 0.5 cm (1/4") below the 10 mL mark. If the transferred volume is lower than 7
mL, the accuracy of the test may be affected. Please repeat the test waiting for longer than
2 minutes to allow complete separation between the two phases.
• Cap the cuvette. This is the reacted sample (#2).
• Fill another cuvette with 10 mL of Chloroform reagent (up to the
mark) and place the cap. This is the blank (#1).
• Place the blank cuvette (#1) into the holder and close the lid.
186
#2
#1 blank
#1