环境化学(英文)100题含答案7页

1、1. What are the roles of atmospheric carbon dioxide?a) CO2 for photosynthesis (光合作用)b) CO2 is the most criticized greenhouse gas (温室气体)2. What are the roles of water vapor in the atmosphere? (书9.5 课件)答：Green house gases.Air with a given relative humidity can undergo any of several processes to reach

2、 the saturation point at which water vapor condenses in the form of rain or snow. Water vapor condenses (rain) as the air cools with the increasing altitude Provide nucleation bodies for condensation of atmospheric water vapor influence upon weather and air pollution.3. What is main absorbent in the

3、 atmosphere to shield the ultraviolet radiation for reaching the Earth surface? Where are they located in the atmosphere?答：O3。 Stratosphere（平流层）。4. Why CO2 is called greenhouse gas?答：能够吸收红外线，保温作用。CO2不吸收短波辐射（可见光、紫外线等），但吸收长波辐射（红外线等）。太阳的短波辐射可直达地球表面，被地表吸收后，以长波辐射的形式向外发射。大气中的CO2吸收了长波辐射后，就将这一部分长波辐射的能量留在大气中

4、，使地表的大气温度升高，如同玻璃温室一样。温室气体的这种功能效应称为温室效应。5. Name three greenhouse gases other than CO2 and H2O.答：CH4、Nitrogen Oxide 、ozone6. What is definition of Lapse（失效） Rate? （课件）答：The Lapse Rate: the decreasing rate of temperature with altitude7. What is the lapse rate of dry air? 答：If there is no condensation o

5、f moisture from the air , the cooling effect is about 10C per 1000 meters of altitude ,a figure know as dry adiabatic lapse rate8. How the lapse rate of humid air compared to that of dry air?答：Adiabatic（绝热） lapse rate of humid air is less than that of dry air（湿空气绝热失效速率小于干空气）9. Relation between the l

6、apse rate and the stability of the air.答：The stable atmosphere has lapse rate less than the adiabatic lapse rate（稳定空气失效速率小于绝热失效速率）10. How does temperature inversion affect the air pollution?答：Temperature Inversion results in air stagnation and the trapping of air pollutants in localized areas 11. Wh

7、at are the removal pathways of air pollutants?答：Oxidation (氧化): Reactions with OH, NO3, O3, O(3P), Cl, Photolysis (光解)Dry Deposition (沉降): Being absorbed by the surfaceWet Deposition: Adsorb onto the air particles and been brought back to the surface by rainfall（干湿沉降）12. What are the main sources an

8、d sinks of CO in the atmosphere?答：2/3 from oxidation of CH4 by OH radical20% from chlorophyll (叶绿素) degradation6% from anthropogenic source（人为因素）a) From internal combustion engineb) Reduced CO emission with high air : fuel ratioc) Catalytic reduction of CO13. In unpolluted air, NO is oxidized to NO2

9、 by O3. What about in the polluted atmosphere?答：In polluted atmosphere, NO is oxidized to NO2 by peroxy radicals ROO 过氧自由基14. What are the three necessary compounds of photochemical smog?答：Ultraviolet light Hydrocarbons Nitrogen oxides15. What are the characteristics of photochemical smog（烟雾）?答：Orig

10、inally, Smog refers to the combination of smoke and fog due to SO2 when high-sulfur coal was burned.1.Characterized by the presence of SO22.A reducing smog or sulfurous smogCurrently, Smog refers to the photochemical smog:1.Occurs in many urban areas2.Characterized by high O3 concentration and low v

11、isibility 能见度3.An oxidizing smog: (1)Oxidant level exceeds 0.15 ppm for more than one hour(2)SO2 has a short lifetime4.Effects: moderate to severe eye irritation16. Sketch the size distribution（分布）of particles in the atmosphere. Explain it briefly.颗粒大沉降速度快，颗粒小容易聚合17. Why do CF4 and SF6 have much hig

12、her radiative forcing that CO2?（1） 吸收光谱和CO2错开 （2）寿命长18. What is the rationale for classifying most acid rain as a secondary pollutant?答：Most of acid rain originated from the secondary air pollutant produced by the atmospheric oxidation of acid-forming gases such as SO2 and NO219. Distinguish among U

13、V-A, UV-B, and UV-C radiation. Why does UV-B pose the greatest danger in the troposphere?UV-B可以被人类DNA和蛋白质所吸收20. How does the oxidizing nature of ozone from smog contribute to the damage that it does to cell membranes（细胞膜）?O3会跟不饱和碳碳双键反应21. What may be said about the time and place of the occurrence o

14、f maximum ozone levels from smog with respect to the origin of the primary pollutants that result in smog formation?答：the place is the stratosphereand the time is noon when NO is at its min concentration22. What particularly irritating product is formed in the laboratory by the irradiation of a mixt

15、ure of benzaldelhyde and NO2 with ultraviolet light? (13.4)答：PBN peroxybenzoyl nitrate23. Which of the following species reaches its peak value last on a smog-forming day: NO, oxidants, hydrocarbons, NO2?答：oxidants24. What is the main species responsible for the oxidation of NO to NO2 in a smoggy at

16、mosphere?答：Peroxyl radicals.25. Increase in temperature can lead to severe O2 depletion in natural water, why?答：At higher temperature, the decreased solubility of oxygen, combined with the increased respiration rate of aquatic organisms, frequently causes a condition in which a higher demand for oxy

17、gen accompanied by lower solubility of the gas in water result in severe oxygen depletion26. How about the biodegradability（生物降解） of humic substances（腐殖质）? Easy or difficult?答：Difficult. Humic substances are degradation-resistant material formed during the decomposition of vegetation that occur as d

18、eposits in soil marsh sediments,peat,coal,lignite or in almost any location where large quantities of vegetation have decayed.27. Humic substances can be classified as _, _, _, according to their solubility in basic and acid solutions. What are their solubility in basic and acid solution?答：腐黑质、腐殖酸、褐

19、菌素28. Can we give a defined structure to humic substances? How do we normally characterize them?答：Humic substances are degradation-resistant materials formed during the decomposition of vegetation that occur as deposits in soil, marsh sediments, peat, coal, lignite, or in almost any location where l

20、arge quantities of vegetation have decayed. Humic substance are high-molecular-weight, polyelectrolytic macromolecules. Molecules weights range from a few hundred for fulvic acid to tens of thousands for the humic acid and humic fraction. These substances contain a carbon skeleton with a high degree

21、 of aromatic character and with a large percentage of the molecular weight incorporated in functional groups, most of which contain oxygen.(3.17)(（1）不能，（2）官能团，分子量，元素组成还包括溶解度)29. Humic substances bind strongly to: Metal Cations 30. What are the sources of surface charge of colloidal particles in aque

22、ous phase?答 ：The surface charges is frequently pH-dependent, around pH 7 most colloidal particles in natural waters are negatively charges. (5.4)31. Aggregation（聚集物） removes colloidal particles from water, to form bottom sediment and to clarify the turbid water. What are the usually ways of aggregat

23、ion?答：Coagulation （凝结）and flocculation（絮结） 32. A sediment（沉淀） sample was equilibrated with a solution of NH4+ ion, and the NH4+ was later displaced by Na+ for analysis. A total of 33.8 milliequivalents of NH4+ were bound to the sediment and later displaced by Na+. After drying, the sediment weighed

24、87.2 g. What was its CEC in milliequivalents/100 g?答：阳离子交换量(CEC) 以每百克干土吸附阳离子的毫克当量数表示(m.e/100g)。CEC cation-exchange capacityECS exchangeable cation status CEC in milliequivalents/100g=33.8/(87.2-33.8)=0.633 (5.8)33. A sediment sample with a CEC of 67.4 milliequivalents/100 g was found to contain the

25、following exchangeable cations in milliequivalents/100 g: Ca2+, 21.3; Mg2+, 5.2; Na+, 4.4; K+, 0.7. The quantity of hydrogen ion, H+, was not measured directly. What was the ECS of H+ in milliequivalents/100 g?答：The ECS of H+ in milliequivalents/100g=67.4-(21.3+5.2+4.4+0.7)=35.8 (5.8)34. What is BOD

26、, and which types of water pollutants contribute most to it?答：The degree of oxygen consumption by microbially-mediated oxidation of contaminants（污染物） in water is called biochemical oxygen demand, BOD. The bacterial pollutant and oxidizable pollutant contribute most to it.（细菌性污染物和氧化性污染物）35. Sketch th

27、e downstream O2 level of dissolved oxygen concentration after the addition of oxidizable pollutants are discharged into the stream at certain site. Sketch the level of oxidizable pollutants as well. Explain them.（1）生物降解（2）溶解氧36. Name two types of organic pollutants.答：1、PCBs; Pesticides, herbicides;

28、Petroleum ,Industrial chemical byproducts, carcinogens37. What do Persistent Organic Pollutants (POPs) mean? Name a few POPs.答：1-POPs have long atmospheric lifetime，Which are vaporized into the atmosphere in warmer region and condense and deposits in the cold regions2-DDT and CFCs、PCB38. Chlorinated

29、 organic compounds are persistent in the environment. Who cautioned us first on their potential environmental impact?答：Molina，Mario.J and F.Sherwood Rowland39. Name at least three compounds persistent in the environment.答：Water 、oxygen、carbon dioxide40. Identify a few sources of waste water.答：.Organ

30、ic Components: Organic chemical waste; Oils ahd greases; Chelating agents;Detergents, soaps, and surfacants; Biocides; Particulate organic particles and coagulants2.Live Components: Bacteria, Viruses, Germs and Microbes3.Eutrifying Components: NO3- and NH3; Phosphate and detergents; Micronutrients4.

31、Inorganic and Organometallics: Heavy metals, Biocides, Salts, Inorganic soluble compounds41. Sketch the wastewater treatment process using the Activated Sludge Process. What types of water pollutants are removed by it?答：1.trinkling filter;rotating biological reactors 2.phosphorus removal42. What is

32、the condition for the Activated Sludge Process: aerobic or anaerobic?Solution: The condition for the Activated Sludge Process is aerobic. Because sewage treatment proesses can be divided into mainstream treatment processes and sidestream pricesses. During sidestream treatment, sludge is dewatered, d

33、egraded, and disinfected by a variety of processes, including gravity thickening , dissolved air flotation, anaerobic digestion , aerobic digeston, vacuum filtration, centrifugation, belt-filter press filtration, and Purifax treatment. Each of these produces a liquid by-product sidestream which is c

34、irculated back to the mainstream. These add to the biochemical oxygen demand and suspended solids of the mainstream.43. What are the purposes in the so-called Advanced Wastewater Treatment or Tertiary Wastewater Treatment?解: Tertiary Wastewater Treatment is a term used to describe a variety of proce

35、sses performed on the effluent from secondary waste treatment. The contaminants removed by tertiary waste treatment fall into the general categories of (1) suspended solids, (2) dissolved organic compounds, and (3) dissolved inorganic materials, including the important class of algal nutrients.44. H

36、ow is soil formed? (CH16.1 PART3 PARA.3 )答：Soil are formed by the weathering of parent rocks as the result of interactive geological, hydrological, and biological processes. Soil are porous water and biological processes, including the production and decay of biomass. Soils are open systems that und

37、ergo continual exchange of matter and energy with the atmosphere, hydrosphere, and biosphere.45. Match the following: (CH16.2 PARA.3 & PARA.5)1. Subsoil (a) Weathered parent rocks from which the soil originated2. Gravels(b) Largest particle size fraction (260 mm) according to the United Classificati

38、on System3. Topsoil(c) B horizon of soil4. C horizon(d) Layer of maximum biological activity in soil that contains most of the soil organic matter答：1-c 2-b 3-d 4-a46. How does the ion-exchange capacity of humus compare to those of other organic matter? (CH16.3 PARA.1)答：Organic materials exchange cat

39、ions because of the presence of carboxylate group and other basic functional groups. Humus typically has a very high cation-exchange capacity. The cation-exchange capacity of peat may range from 300-400 meq/100 g. Values of cation-exchange capacity for soils with more typical levels of organic matte

40、r are around 10-30 meq/100 g.47. Of the following phenomena, the one that eventually makes soil more basic is (a) removal of metal cations by roots, (b) leaching of soil with CO2-saturated water, (c) oxidation of soil pyrite, (d) fertilization with (NH4)2SO4, (e) fertilization with KNO3.答： C48. What

41、 are the characteristics of micronutrients?答：Micronutrients are elements needed by plants only at very low level and frequently are toxic at higher levels 49. Seldom are living organisms exposed to s single toxic pollutant. What are the possible types of combined effects when living organisms are ex

42、posed to more than two or more pollutant simultaneously?50. What parameters can be obtained from the Dose-response curve?答：the percentage of death of organismsthe does of the toxicant 51. Two toxicants have LD50 of 100mg/kg and 1mg/kg, respectively. Which one is more toxic?答：The one the LD50 is 1mg/

43、L is more toxic52. The metabolism of xenobiotics in body is often referred to as biotransformation which is usually classified as enzyme-catalyzed Phase I and Phase II reactions. Briefly describe the Phase I and Phase II reactions.答：Phase 1 is definited as reactions, which make the lipophilic xenobi

44、otic species in the body more water-soluble and reactive by the attachment of polar functional groups, such as OH ion.Phase 2 is definited as reactions, which are called conjugation reaction in which enzymes attach conjugating agents to xenobiotics53. Concepts: teratogenesis, mutagenesis, and carcinogenesis.答：Cancer is a condition characterized by the uncontr