final_quiz2

final_quiz2 - 1.725 Chemical Fate and Transport in the...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
1.725 Chemical Fate and Transport in the Environment Quiz #2 Dec. 14, 2004 9am-12am. 1) (15 pts) Wind from over the ocean has a temperature of 17 degrees C and a relative humidity of 85 %. Orographic effects direct this air to rise to a maximum altitude 2500 meters, after which it descends to an altitude of 500 meters on the lee side of the coastal mountains. a) If this is typical of average conditions, at what altitude do you expect to see the beginning of the rainforest on the windward side of the mountain range? b) What is the temperature of air as it reaches the 500 meter level in the desert located on the lee side of the mountains? 2) (10 pts) The tanker Ever Reward is leaking its cargo of the pesticide Parathion. The attending Coast Guard official (who has taken a few environmental science classes) says not to worry about the pesticide; it will undergo hydrolysis in the water and be degraded within a few weeks. The company representative says not to worry, photolysis will quickly degrade the pesticide. Does either (or both) mode of degradation seem likely, based on the chemical structure of Parathion? (explain) Parathion O (CH 3 CH 2 O) 2 P S NO 2
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
3. (15 pt) The compound, dichloromethylacetate, Cl 2 CHCOOCH 3 , undergoes hydrolysis with rate constants as follows: k a is 2.3x10 -4 M -1 s -1 , k n is 1.5x10 -5 s -1 , and k b is 2.8x10 +3 M -1 s -1 . a) What is the hydrolysis half-life of dichloromethylacetate in water at pH 7.8? b) A mole of the compound, together with a mole of a tracer, sodium bromide, are spilled into a canal whose average velocity is 0.91 m/s (3 ft/s) and discharge is 0.84 m 3 /s (30 ft 3 /s). If the Manning coefficient is .020 and width is 3 m (10 ft.), determine the slope of the rectangular channel. (note- this Manning coefficient of 0.20 works with the traditional engineering units, not SI units) c) What is u* for the canal? d) What are maximum bromide and dichloromethylacetate concentrations expected 0.5 km downstream, assuming pH = 7.8?
Background image of page 2
4. (15 pt) An aquifer cleanup program requires that you design a well that will create a hydraulic gradient of 0.009 at a distance of 45 m from the well at steady state. Assume a radius of influence of 200 m. (This gradient will assure the capture of a cloud of perchloroethylene.)
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 11/21/2009 for the course CEE 432 taught by Professor Ahmed during the Spring '09 term at Rowan.

Page1 / 11

final_quiz2 - 1.725 Chemical Fate and Transport in the...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online