Question

A hazardous chemical was spilled into a quiescent pond. The chemical is immiscible with
water and has a density of 0.9 g cm−3. A haz mat team estimated that there is a layer of the
chemical on the pond surface that is 2 cm in thickness. Measurements made with a portable
gas chromatograph show that the vapor film layer above the surface of this chemical layer is
about 0.5 cm in thickness. The diffusivity of this chemical in air is known to be 0.03 cm2 s−1.
Since the pond is in a remote location, it has been decided to just let the chemical evaporate
into the air. Assuming the concentration of the chemical in the bulk air is so low that it can be
neglected, estimate how many days this will take. The saturation concentration of the chemical
in the air is 6.73 × 10−5 g cm−3.

Answer 1

Answer '- Cm per uni area 24メ260D