To determine partition coefficient of Naphthalene using shake flask method B.Pharmacy 4th Semester 2022 (2021-2022) Previous Year's Question Papers/Notes Download - HK Technical PGIMS

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Aim: To determine partition coefficient of Naphthalene using shake flask method.

Requirements: Laboratory stand, separatory funnel (500 ml), calibrated cylinder (50 ml,
500 ml), funnel, beaker (500 ml, 100 ml), vial, mini-vial, automatic pipette, distilled water.

Theory: The octanol-water partition coefficient, Koy, describes equilibrium partitioning of a
chemical between octanol and water phases. It is an important parameter used in the
assessment of environmental fate and transport of organic chemicals because the octanol
phase is a surrogate for the lipid phase or organic carbon content of the environmental
compartments. Kow is one of the most important physico-chemical characteristics related to
sorption on the soil or sediments, and bioaccumulation. Koy is defined as an equilibrium
ratio of the concentration in the octanol phase, C, (ug ml”) and its concentration in the
aqueous phase, C,, (ug mL”), by the equation: Koy = i

Procedure:

¢ Dissolve 0.011 g of naphthalene in 5 ml of octanol.
© Sonicate the naphthalene solution (5 min).
* Fill the naphthalene solution and 500 ml of distilled water in a separatory funnel.
e Shake the mixture for 10 min.
Note: Hold the funnel tightly at the stopper and the stopcock.
© Invert slowly and vent (open the stopcock) towards the back of the hood to release
the pressure.
* Close the stopcock and shake the funnel gently, then vent again.
Repeat this step until no more gas is released,
Separate the octanol and water phases into the beakers.

Result: