Quantitative equilibrium calculations

Fundamentals
Problems
      Fraction of atrazine
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           Answer
     Retardation factor
           Answer
     Raining out
           Answer
     Carpet
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           Answer
     Sorption kinetics
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           Answer
     Organic pollutants in water
           Answer
     Fish toxicity test
           Answer
     Ethylacetate
           Answer
     Tetrachlorobenzene
           Answer
     Hexachlorobenzene
           Answer
     Chlorobenzene
           Answer
     Toxicity test
           Answer
     Toxicity test - improving...
     3 phases problem
           Answer
     Sorption experiment
           Answer
     HCH
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Minesweeper-problems

Hexachlorobenzene

A concentration of 100 µg hexachlorobenzene (HCB) per kg wet weight has been measured in fish that live and in the sediment/water interface. The average fat content of the fish is about 5 %  (i.e. 0.05 kg lipid per kg wet weight). The aqueous concentration of HCB in water was determined to be 0.1 ng L-1, in the sediment (foc = 0.05 kgockg-1 in dry sediment) a concentration of 2 µg kg-1 sediment (dry) was analysed.

Estimate (roughly) which concentration one would expect in the fish (in µg per kg wet weight) if they were in equilibrium with
a) the water phase or
b) the sediment phase.

What assumptions do you make?

 

Use the following partition constants:

log Klipid/water = 5.8 (Lwater/Llipid)

log Koc/water = 5.3 (Lwater/kgoc)