ChemicalFormulas - In Manual Method to reduce evaporation loss of the distillate, cover the
receiving cylinder with a piece of blotting paper, or similar
material, that has been cut to fit the condenser tube snugly. If a receiver deflector
is being used, start the distillation with the tip of the deflector just
touching the wall of the receiving cylinder. If a receiver deflector is not
used, keep the drip tip of the condenser away from the wall of the receiving
cylinder. Note the start time. Observe and record the IBP to the nearest 0.5°C
(1.0°F). If a receiver deflector is not being used, immediately move the
receiving cylinder so that the tip of the condenser touches its inner wall.
In Automated
Method Of Distillation Apparatus - To reduce evaporation loss of the
distillate, use the device provided by the instrument manufacturer for this
purpose. Apply heat to the distillation flask and contents with the tip of the
receiver deflector just touching the wall of the receiving cylinder. Note the
start time. Record the IBP to the nearest 0.1°C (0.2°F).
For an automateddistillation apparatus, the level follower/recording mechanism of the apparatus
shall have a resolution of 0.1 mL or better with a maximum error of 0.3 mL
between the 5 and 100 mL points. The calibration of the assembly shall be verified
in accordance with manufacturer’s instructions at intervals of not more than
three months and after the system has been replaced or repaired.
Barometer as a pressure measuring device capable of measuring local
station pressure with an accuracy of 0.1 kPa (1 mm Hg) or better, at the same
elevation relative to sea level as the apparatus in the laboratory. At
intervals of not more than six months, and after the system has been replaced
or repaired, the barometric reading of the instrument shall be verified again.
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