Question

A jar containing 3.1 kg of mercury is dropped into a lake that is 43,000 ft2and has an average depth of 4.2 ft. Water flows into and out of the lake at 1.6 ft3/s maintaining a constant volume. Assuming the mercury completely dissolves (very poor assumption in reality) and that the lake is completely mixed, what is the mercury concentration in the lake (in mg/L) (a) immediately after the exposure and (b) 5 days later. (c) How long would it take for the lake to meet the Water Quality Criteria of 0.77 μg/L.

Answer 1