CBSE NET Environmental-Science June-2012 Solved Paper III

  1. If the standard deviation of a population is 20, the population and sample means are 35 and 33, respectively and the t-statistic at 95% confidence level is

  2. 5, the sample size is

    1. 100

    2. 125

    3. 250

    4. 625

    Answer: d

  3. For 5 degrees of freedom, the variance of c2 distribution is

    1. 10

    2. 5

    3. 16

    4. 4

    Answer: a

  4. Identify the random sampling method among the following:

    1. Judgement sampling

    2. Quota sampling

    3. Convenience sampling

    4. Stratified sampling

    Answer: a

  5. At higher pH, majority of iron is present as

    1. Fe2 +

    2. Fe3 +

    3. Fe2 + and Fe3 +

    4. Fe (OH) 2 and Fe (OH) 3

    Answer: d

  6. In living organisms phosphorous is largely assocated with

    1. Carbohydrate

    2. Lipids

    3. Nucleic acids

    4. Proteins

    Answer: c

  7. Molar extinction coefficient of malondialdehyde at 532 nm is 0.155 M–1cm–1. The concentration of malondialdehyde in a solution which has absorbance of 0.31 in a 1 cm curette will be

    1. 0.5 M

    2. 1.0 M

    3. 1.5 M

    4. 2.0 M

    Answer: d

  8. pOH of 0.001 M solution of HCl is

    1. 0.1

    2. 1

    3. 10

    4. 11

    Answer: d

  9. The molecular weight of DDT is 354.5. The quantity of DDT required to prepare one litre of 10 ppm DDT solution is

    1. 10 mg

    2. 35.45 mg

    3. 354.5 mg

    4. 354.5 μg

    Answer: a

  10. Which one of the following is referred to as superoxide radical?

    1. O

    2. O2

    3. O° –2

    4. O3

    Answer: c

  11. The net primary productivity of an ecosystem is

    1. the gross primary productivity minus plant respiration

    2. the primary productivity at herbivore level

    3. the primary productivity at consumer level

    4. the productivity at top consumer level minus respiration at all levels

    Answer: a

  12. Which of the following habitats has not been included as Indian biodiversity hot spots?

    1. The Eastern Ghats

    2. The Western Ghats

    3. North-Eastern Hills

    4. South-Eastern Hills

    Answer: d

  13. The area of the biosphere which is protected entirely, without any experimentation and research and no biotic interference, is known as

    1. Undisturbed zone

    2. Buffer zone

    3. Core zone

    4. Principal zone

    Answer: c

  14. When a mixture of Azospirillum, Azotobacter and Vibrio was applied to rhizosphere, fixation of atmospheric nitrogen was increased. It was due to activity of

    1. All the three

    2. Azospirillum and Vibrio

    3. Azotobacter and Vibrio

    4. Azotobacter and Azospirillum

    Answer: d

  15. Which type of forests are found at an altitude of 5300 ft chiefly on mountains of Himalayas and Nilgiri?

    1. Dry deciduous forest

    2. Moist tropical forest

    3. Temperate forest

    4. Tropical moist deciduous forest

    Answer: c

  16. The sequence of events that occur during primary succession is as follows:

    1. Nudation – Colonisation – Ecesis – Aggregation

    2. Aggregation – Colonization – Ecesis – Nudation

    3. Ecesis – Nudation – Aggregation – Colonization

    4. Nudation – Ecesis – Colonization – Aggregation

    Answer: d

  17. As per Raunkaiers law of frequency, five different frequency classes (A, B, C, D and E) in a natural undisturbed community exhibit one of the following relationship:

    1. A < B > C > = < D < E

    2. A > B > C > = < D < E

    3. A < B > C > = < D > E

    4. A < B < C > = < D > E

    Answer: b

  18. Which one of the following category of earthworms is most suitable for Vermicomposting?

    1. Epigeic

    2. Anecic

    3. Endogeic

    4. All the above

    Answer: a

  19. Which one of the following is an in situ method of biodiversity conservation?

    1. Reserve forest

    2. National parks

    3. Sanctuaries

    4. All the above

    Answer: d

  20. Match the contaminant in Column – I with the disease in Column – II:

    List-I List-II
    1. Mercury

    2. Nitrate Nitrogen

    3. Cadmium

    4. Coal

    1. Methamoglobinemia

    2. Itai Itai

    3. Silicosis

    4. Minamata

    • A
    • B
    • C
    • D
      • 2
      • 3
      • 4
      • 1
      • 3
      • 4
      • 2
      • 1
      • 1
      • 2
      • 3
      • 4
      • 4
      • 1
      • 2
      • 3

    Answer: d

  21. Which of the following types of coal contains higher percentage of volatile matter?

    1. Peat

    2. Lignite

    3. Bituminous

    4. Anthracite

    Answer: a

  22. Carbon dioxide evolved from soil mainly comes from

    1. Microbial respiration

    2. Root respiration

    3. Soil animals respiration

    4. All the above

    Answer: a

  23. Which one of the following pesticides persists for a long period in soil?

    1. Lindane

    2. Monocrotophos

    3. Carbaryl

    4. Parathion

    Answer: a

  24. Organic matter (OM) content of sol can be calculated from organic carbon (OC) by using the formula

    1. OM (%) = OC (%) × 1.724

    2. OM (%) = OC (%) × 1.247

    3. OM (%) = OC (%) × 1.472

    4. OM (%) = OC (%) × 1.427

    Answer: a

  25. The problem of thermal pollution can be alleviated by using

    1. Cooling ponds

    2. Cooling towers

    3. More efficient electricity generating plants

    4. All the above

    Answer: d

  26. According to Recycled Plastics (Manufacture and Usage) Rules 1999, the minimum thickness of carry bags shall not be less than

    1. 10 microns

    2. 20 microns

    3. 30 microns

    4. 50 microns

    Answer: b

  27. Match the Act mentioned in Column – I with the year of enactment mentioned in Column – II:

    List-I List-II
    1. The Water (Prevention and Control of Pollution) Act

    2. The Air (Prevention and Control of Pollution) Act

    3. The Environmental (Protection) Act

    4. The Biological Diversity Act

    1. 2002

    2. 1986

    3. 1974

    4. 1981

    • A
    • B
    • C
    • D
      • 1
      • 4
      • 3
      • 2
      • 3
      • 4
      • 2
      • 1
      • 3
      • 2
      • 1
      • 4
      • 2
      • 4
      • 3
      • 1

    Answer: c

  28. Which one of the following is not an energy recovery method of solid waste management?

    1. Pelletisation

    2. Biomethanation

    3. Pyrolysis

    4. Composting

    Answer: d

  29. The colour code of the container for collection of waste scrap generated from Hospitals is

    1. Red

    2. Blue

    3. White

    4. Green

    Answer: b

    • Assertion (A): When quantitative probabilistic risk assessment is performed on hazardous waste sites they usually turn out to be of relatively low threats.
    • Reason (R): In hazardous waste sites the chance of exposure is low because of isolation of drinking water supplies and prevention of access.
    1. Both (A) and (R) are true and (R) is the correct explanation of (A).

    2. Both A and R are true, but R is not the correct explanation of (A).

    3. A is true, but R is false.

    4. A is false, but R is true.

    Answer: a

  30. In India, an Environment Impact Assessment report of a proposed mining project after environmental clearance is applicable for a maximal period of how many years?

    1. 5 years

    2. 10 years

    3. 30 years

    4. 2 years

    Answer: c

  31. An increase of one unit of Richter Scale represents an increase in amplitude by a factor of

    1. 10

    2. 100

    3. 1000

    4. 2

    Answer: a

  32. Which rare earth element is not present in the earth's crust but for commercial purpose comes from the Nuclear reactors?

    1. Promethium

    2. Lanthanum

    3. Cerium

    4. Samarium

    Answer: a

  33. To display green colour in the monitor the amount of RGB should be

    1. 255: 0: 0

    2. 255: 255: 255

    3. 0: 0: 0

    4. 0: 255: 0

    Answer: d

  34. When the temperature range in geothermal resource is generally low, electrical power generation from such resources require the use of secondary low boiling point fluid. This is generally known as

    1. Rankine cycle

    2. Production well cycle

    3. Flash stem cycle

    4. Hard Dry Rock cycle

    Answer: a

  35. The Global Warming Potential (GWP) is the least for which of the following greenhouse gases?

    1. CH4

    2. CO2

    3. N2O

    4. SF6

    Answer: b

  36. The maximum specific power output (p) from a MHD power generator varies with the velocity (u) of hot ionized gas as

    1. pµ u

    2. p µ u2

    3. p µ u3/2

    4. p µ u3

    Answer: b

    • Assertion (A): Electrostatic precipitators (ESPs) can be harmful if not operated properly.
    • Reason (R): Corona discharge in ESPs produces ozone.
    1. A Both (A) and (R) are correct and (R) is the correct explanation of (A).

    2. Both A and R are correct and R is not the correct explanation of (A).

    3. A is true, but R is false.

    4. Both A and R are false.

    Answer: a

    • Assertion (A): Vegetation hedges are the best way to control noise.
    • Reason (R): Vegetation hedges scatter noise. Choose the correct answer.
    1. Both A and R are correct and R is the correct explanation of (A).

    2. Both A and R are correct, but R is not the correct explanation of (A).

    3. A is true, but R is false.

    4. A is false, but R is true.

    Answer: d

  37. If w and ws are mixing ratio and saturation mixing ratio respectively; T and Td are the ambient temperature and dew point temperature respectively, then identify the correct expression of relative humidity (RH).

    1. RH = (w at Td)/(w at T)

    2. RH = (w at T)/(w at Td)

    3. RH = (ws at Td)/(ws at T)

    4. RH = (ws at T)/(ws at Td)

    Answer: c

  38. Identify mesoscale phenomenon.

    1. Tornado

    2. Sea breeze

    3. Cyclone

    4. Eddies

    Answer: b

  39. For elevations less than few hundred metres, if the wind speeds are u1 and u2 at elevations z1 and z2 respectively, the following equation holds u1/u2 = (z1/z2) p. The value of the exponent p is

    1. < 0.6

    2. = 1

    3. > 0.6

    4. negative

    Answer: a

    • Assertion (A): Noise gets attenuated more in dry atmosphere.
    • Reason (R): Moist air is less denser than dry air.
    1. A Both (A) and (R) are true and (R) is the correct explanation of (A).

    2. Both A and R are true and R is not the correct explanation of (A).

    3. A is true, but R is false.

    4. A is false, but R is true.

    Answer: b

  40. OH • = radicals in atmosphere play a role of

    1. scavenger

    2. acidifier

    3. reducing agent

    4. greenhouse gas

    Answer: a

  41. The slow neutrons initiating nuclear fisson with U235 have energies of the order of

    1. 0.25 MeV

    2. 0.15 MeV

    3. 0.25 eV

    4. 0.025 eV

    Answer: d

  42. The most suitable range of wind speeds for wind power generation is

    1. 1 – 5 m/s

    2. 4 – 12 m/s

    3. 10 – 20 m/s

    4. 20 – 50 m/s

    Answer: b

  43. For energy to be produced from nuclear fusion of Deuterium (D) and Tritium (T), the mixture of D + T has to be heated up to energies of at least

    1. 1 KeV

    2. 10 KeV (C) 500 eV

    (D) 1 MeV

    Answer: b

  44. Element contaminating the water body is determined and quantified by using one of the following methods:

    1. Colorimeter

    2. Spectrophotometer

    3. Atomic absorption spectrometer

    4. All the above

    Answer: d

  45. In which type of chromatography four modes viz, Absorption, partition, Ion exchange and exclusion, are present?

    1. HPLC

    2. Liquid-liquid chromatography

    3. Ion-exchange chromatography

    4. Adsorption chromatography

    Answer: a

  46. The metal which is generally absorbed by plants along with Zn and causes “Ouch Ouch” disease in human beings is

    1. Pb

    2. Cd

    3. Hg

    4. Cr

    Answer: b

  47. Radioactive isotopes of which of the elements in human body decay every second?

    1. K40 and C14

    2. C14 and N6

    3. N16 and K40

    4. None of the above

    Answer: a

  48. Which of the following techniques is most appropriate for determining crystalline structure of environmental samples?

    1. Infrared spectroscopy

    2. X-ray diffraction

    3. Microspectrophotometry

    4. Raman spectroscopy

    Answer: b

  49. Which one of the following is the most predominant element in a majority of igneous rocks?

    1. Al

    2. Fe

    3. O

    4. Si

    Answer: c

  50. Match the entries in Group-I with the process parameters in Group-II:

    List-I List-II
    1. Clark electrode

    2. Redox Probe

    3. Load cell

    4. Diaphragmn gauge

    1. Dissolved Oxygen

    2. pH

    3. Liquid level

    4. Vessel pressure

    • A
    • B
    • C
    • D
      • 1
      • 2
      • 3
      • 4
      • 2
      • 1
      • 4
      • 3
      • 1
      • 4
      • 3
      • 2
      • 4
      • 3
      • 2
      • 1

    Answer: a

  51. Which one of the following is used to determine total organic matter by Walkley and Black method?

    1. KOH and H2SO4

    2. Na2S2O3 and H2SO4

    3. K2Cr2O7 and H2SO4

    4. HNO3 and H2SO4

    Answer: c

  52. As per WHO standards the maximum permissible level of coliform organisms per 100 ml of drinking water is

    1. 10

    2. 100

    3. 150

    4. 1000

    Answer: a

  53. Progressive increase in concentration of a xenobiotic compound when it passes through the food chain is called

    1. Biomagnification

    2. Hyper accumulation

    3. Bioaccumulation

    4. None of the above

    Answer: a

  54. Highest level of biotic interaction is

    1. Mutualism

    2. Predation

    3. Parasitism

    4. Amensalism

    Answer: b

  55. Which one of the following is considered as indicator of aquatic pollution?

    1. Rotifers

    2. Copepods

    3. Mysids

    4. Calanoids

    Answer: a

  56. Poorly nourished lakes are known as

    1. Oligotrophic

    2. Eutrophic

    3. Mesotrophic

    4. Xerotrophic

    Answer: a

  57. Identify a sampling method which is not non-destructive.

    1. Sub-surface coring

    2. Using of neutron probes to measure soil water

    3. Fourier transform infrared spectroscopy

    4. Time domain refractometry to measure soil water

    Answer: a

  58. Ministry of Environment and Forests amended the EIA notification making public hearing mandatory for environmental clearance on

    1. 27th January 1996

    2. 10th April 1997

    3. 27th January 1997

    4. None of the above

    Answer: b

  59. The allochthonous microorganisms of an ecosystem are

    1. Indigenous microorganisms

    2. Migrant

    3. Parasitic

    4. Pathogenic

    Answer: b

  60. The rate of evaporation of oil spilled into the sea depends on

    1. The elemental concentration of sea water

    2. The composition of sea water microflora

    3. Composition of the crude oil

    4. The temperature of the sea

    Answer: c

  61. The most dangerous and heat resistant spoilage organism in canning industry is

    1. Clostridium cellulolyticum

    2. Bacillus subtilis

    3. E. Coli

    4. Clostridium botulinum

    Answer: d

  62. Oxygen concentrations in compost developed in static piles usually

    1. Ten times lower than in ambient air

    2. Five times lower than in ambient air

    3. Two times more than in ambient air

    4. Five times more than in ambient air

    Answer: b

  63. If a bacterium with a 20 minute generation time is grown under optimal conditions (37° C), one cell would multiply to 103 (1000) cells in 3.3 hours, then how much time it will take to multiply to 106 cells?

    1. 5.3 hrs.

    2. 6.6 hrs.

    3. 9.9 hrs.

    4. 6.3 hrs.

    Answer: b

  64. The biodegradation of plant material is slow because of presence of

    1. Cellulose

    2. Xylene

    3. Extensin/protein

    4. Lignin

    Answer: d

  65. The widely used aerobic suspension type of liquid waste treatment system is

    1. Rotating Biological Contactor (RBC)

    2. Percolating filter

    3. Activated sludge process

    4. Septic tank

    Answer: c

  66. The treatment designed to remove nonbiodegradable organic pollutants and mineral nutrients from waste water is

    1. Lagoons

    2. Imhoff tank

    3. Secondary treatment

    4. Tertiary treatment

    Answer: d

  67. An ecotype is

    1. Genetically different forms of the same organisms

    2. Genetically similar forms of the same organisms

    3. Morphologically different forms of the same organisms

    4. Both A and (B)

    Answer: a

  68. Ultraviolet radiations are lethal due to inactivation of

    1. Proteins, nucleic acids and pigments

    2. Minerals, water and air

    3. Carbohydrates, fats and vitamins

    4. O2, CO2 and water

    Answer: a

  69. The following are the characters of species diversity:

    1. More richness

    2. More evenness

    3. More dominance

    4. Less dominance

    5. Less rchness

    6. Less evenness

    Point out the combination of conditions in which species diversity of an ecosystem will be more.

    1. 1, 2 and 3

    2. 5, 2 and 3

    3. 1, 2 and 4

    4. 1, 6 and 4

    Answer: c

    • Assertion (A): If natality is greater than mortality, it leads to population explosion.
    • Reason (R): The scientific study of various species of human population is called demography.
    1. A Both (A) and (R) are true and (R) is the correct explanation of (A).

    2. Both A and R are true, but R is not the correct explanation of (A).

    3. A is true, but R is false.

    4. Both A and R are false.

    Answer: b

  70. Match Column – I with Column – II:

    List-I List-II
    1. Chipko Movement

    2. Narmada Bacchao Andolan

    3. Climate Change

    4. Silent Spring

    1. Medha Patkar

    2. Al Gore

    3. Rachel Carson

    4. Sundarlal Bahuguna

    • A
    • B
    • C
    • D
      • 1
      • 2
      • 3
      • 4
      • 2
      • 3
      • 4
      • 1
      • 4
      • 1
      • 2
      • 3
      • 3
      • 4
      • 1
      • 2

    Answer: c