Chapter 14

The processes of calcination and roasting in metallurgical industries, respectively, can lead to : (a) Global warming and photochemical smog (b) Global warming and acid rain (c) Photochemical smog and ozone layer depletion (d) Photochemical smog and global warming

The presence of soluble fluoride ion upto 1 ppm concentration in drinking water, is : (a) harmful for teeth (b) harmful to skin (c) harmful to bones (d) safe for teeth

Thermal power plants can lead to : (a) Acid rain (b) Blue baby syndrome (c) Ozone layer depletion (d) Eutrophication

The condition that indicates a polluted environment is: (a) eutrophication (b) \(0.03 \%\) of \(\mathrm{CO}_{2}\) in the atmosphere (c) BOD value of \(5 \mathrm{ppm}\) (d) \(\mathrm{pH}\) of rain water to be \(5.6\)

The incorrect statement(s) among (1) - (4) regarding acid rain is (are) : (1) It can corrode water pipes. (2) It can damage structures made up of stone. (3) It cannot cause respiratory ailments in animals (4) It is not harmful for trees (a) (1), (3) and (4) (b) (3) only (c) (1), (2) and (4) (d) (3) and (4)

Biochemical Oxygen Demand (BOD) is the amount of oxygen required (in ppm): (a) for sustaining life in a water body. (b) by bacteria to break-down organic waste in a certain volume of a water sample. (c) for the photochemical breakdown of waste present in \(1 \mathrm{~m}^{3}\) volume of a water body. (d) by anaerobic bacteria to breakdown inorganic waste present in a water body.

The statement that is not true about ozone is : (a) in the stratosphere, CFCs release chlorine free radicals (Cl) which reacts with \(\mathrm{O}_{3}\) to give chlorine dioxide radicals. (b) in the atmosphere, it is depleted by CFCs. (c) in the stratosphere, it forms a protective shield against UV radiation. (d) it is a toxic gas and its reaction with NO gives \(\mathrm{NO}_{2}\).

Among the gases (a)-(e), the gases that cause greenhouse effect are: (1) \(\mathrm{CO}_{2}\) (2) \(\mathrm{H}_{2} \mathrm{O}\) (3) \(\mathrm{CFCs}\) (4) \(\mathrm{O}_{2}\) (5) \(\mathrm{O}_{3}\) (a) (1), (2), (3) and (4) (b) (1), (2), (3) and (5) (c) (1) and (4) (d) (1), (3), (4) and (5)

The correct set of species responsible for the photochemical smog is : (a) \(\mathrm{N}_{2}, \mathrm{NO}_{2}\) and hydrocarbons (b) \(\mathrm{CO}_{2}, \mathrm{NO}_{2}, \mathrm{SO}_{2}\) and hydrocarbons (c) \(\mathrm{NO}, \mathrm{NO}_{2}, \mathrm{O}_{3}\) and hydrocarbons (d) \(\mathrm{N}_{2}, \mathrm{O}_{2}, \mathrm{O}_{3}\) and hydrocarbons

The concentration of dissolved oxygen (DO) in cold water can go upto (a) \(14 \mathrm{ppm}\) (b) \(8 \mathrm{ppm}\) (c) \(10 \mathrm{ppm}\) (d) \(16 \mathrm{ppm}\)

The primary pollutant that leads to photochemical smog is: (a) acrolein (b) nitrogen oxides (c) ozone (d) sulphur dioxide

Water filled in two glasses \(\mathrm{A}\) and \(\mathrm{B}\) have \(\mathrm{BOD}\) values of 10 and 20 , respectively. The correct statement regarding, them, is: (a) \(\mathrm{B}\) is more polluted than \(\mathrm{A}\). (b) \(\mathrm{A}\) is suitable for drinking, whereas \(\mathrm{B}\) is not. (c) Both A and B are suitable for drinking. (d) \(\mathrm{A}\) is more polluted than \(\mathrm{B}\).

The regions of the atmosphere, where clouds are formed and where we live, respectively, are : (a) Troposphere and Stratosphere (b) Stratosphere and Troposphere (c) Troposphere and Troposphere (d) Stratosphere and Stratosphere

Air pollution that occurs in sunlight is : (a) reducing smog (b) acid rain (c) oxidizing smog (d) fog

Which of the following conditions in drinking water causes methemoglobinemia? (a) \(>50 \mathrm{ppm}\) of lead (b) \(>50\) ppm of chloride (c) \(>50\) ppm of nitrate (d) \(>100 \mathrm{ppm}\) of sulphate

Excessive release of \(\mathrm{CO}_{2}\) into the atmosphere results in: (a) global warming (b) polar vortex (c) formation of smog (d) depletion of ozone

The \(\mathrm{pH}\) of rain water, is approximately: (a) \(5.6\) (b) \(7.5\) (c) \(7.0\) (d) \(6.5\)

The layer of atmosphere between \(10 \mathrm{~km}\) to \(50 \mathrm{~km}\) above the sea level is called as: (a) troposphere (b) thermosphere (c) stratosphere (d) mesosphere

The recommended concentration of fluoride ion in drinking water is up to lppm as fluoride ion is required to make teeth enamel harder by converting \(\left[3 \mathrm{Ca}_{3}\left(\mathrm{PO}_{4}\right)_{2} \cdot \mathrm{Ca}(\mathrm{OH})_{2}\right]\) to : (a) \(\left[\mathrm{CaF}_{2}\right]\) (b) \(\left[3\left(\mathrm{CaF}_{2}\right) \cdot \mathrm{Ca}(\mathrm{OH})_{2}\right]\) (c) \(\left[3 \mathrm{Ca}_{3}\left(\mathrm{PO}_{4}\right)_{2} \cdot \mathrm{CaF}_{2}\right]\) (d) [3\\{ \(\left.\left(\mathrm{Ca}(\mathrm{OH})_{2}\right\\} \cdot \mathrm{CaF}_{2}\right]\)

Which is wrong with respect to our responsibility as a human being to protect our environment? (a) Restricting the use of vehicles (b) Avoiding the use of floodlighted facilities (c) Setting up compost tin in gardens. (d) Using plastic bags.

Biochemical oxygen demand(BOD) value can be a measure of water pollution caused by the organic matter. Which of the following statements is correct? (a) Polluted water has BOD value higher than 10 ppm (b) Aerobic bacteria decreases the BOD value (c) Anaerobic bacteria increases the BOD value (d) Clean water has BOD value higher than \(10 \mathrm{ppm}\)

The molecule that has minimum/no role in the formation of photochemical smog, is: (a) \(\mathrm{N}_{2}\) (b) \(\mathrm{CH}_{2}=\mathrm{O}\) (c) \(\mathrm{O}_{3}\) (d) NO

The compound that is NOT a common component of photochemical smog is: (a) \(\mathrm{O}_{3}\) (b) \(\mathrm{H}_{3} \mathrm{C}-\stackrel{\mathrm{C}}{\|}_{\mathrm{O}}-\mathrm{OONO}_{2}\) (c) \(\mathrm{CH}_{2}=\mathrm{CHCHO}\) (d) \(\mathrm{CF}_{2} \mathrm{Cl}_{2}\)

The upper stratosphere consisting of the ozone layer protects us from the sun's radiation that falls in the wavelength region (a) \(200-315 \mathrm{~nm}\) (b) \(400-550 \mathrm{~nm}\) (c) \(0.8-1.5 \mathrm{~nm}\) (d) \(600-750 \mathrm{~nm}\)

BOD stands for : (a) Biochemical Oxidation Demand (b) Biological Oxygen Demand (c) Biochemical Oxygen Demand (d) Bacterial Oxidation Demand

Peroxyacetyl nitrate (PAN), an eye irritant, is produced by : (a) Classical smog (b) Acid rain (c) Organic waste (d) Photochemical smog

Addition of phosphate fertilisers to water bodies causes: (a) increase in amount of dissolved oxygen in water (b) deposition of calcium phosphate (c) increase in fish population (d) enhanced growth of algae

Taj Mahal is being slowly disfigured and discoloured. This is primarily due to : (a) Global warming (b) Acid rain (c) Water pollution (d) Soil pollution

The higher concentration of which gas in air can cause stiffness of flower buds? (a) \(\mathrm{NO}_{2}\) (b) \(\mathrm{CO}_{2}\) (c) \(\mathrm{SO}_{2}\) (4) \(\mathrm{CO}\)

The reaction that is NOT involved in the ozone layer depletion mechanism in the stratosphere is: (a) \(\mathrm{CF}_{2} \mathrm{Cl}_{2}(\mathrm{~g}) \stackrel{\text { uv }}{\longrightarrow} \dot{\mathrm{Cl}}(\mathrm{g})+\dot{\mathrm{CF}}_{2} \mathrm{Cl}(\mathrm{g})\) (b) \(\mathrm{ClO}(\mathrm{g})+\mathrm{O}(\mathrm{g}) \longrightarrow \dot{\mathrm{Cl}}(\mathrm{g})+\mathrm{O}_{2}(\mathrm{~g})\) (c) \(\mathrm{CH}_{4}+2 \mathrm{O}_{3} \longrightarrow 3 \mathrm{CH}_{2}=\mathrm{O}+3 \mathrm{H}_{2} \mathrm{O}\) (d) \(\mathrm{HOCl}(\mathrm{g}) \stackrel{\mathrm{hv}}{\longrightarrow} \dot{\mathrm{O}} \mathrm{H}(\mathrm{g})+\dot{\mathrm{Cl}}(\mathrm{g})\)

Which of the following is a set of green house gases? (a) \(\mathrm{CH}_{4}, \mathrm{O}_{3}, \mathrm{~N}_{2}, \mathrm{SO}_{2}\) (b) \(\mathrm{O}_{3}, \mathrm{~N}_{2}, \mathrm{CO}_{2}, \mathrm{NO}_{2}\) (c) \(\mathrm{O}_{3}, \mathrm{NO}_{2}, \mathrm{SO}_{2}, \mathrm{Cl}_{2}\) (d) \(\mathrm{CO}_{2}, \mathrm{CH}_{4}, \mathrm{~N}_{2} \mathrm{O}, \mathrm{O}_{3}\)

Identify the pollutant gases largely responsible for the discoloured and lustreless nature of marble of the Taj Mahal. (a) \(\mathrm{O}_{3}\) and \(\mathrm{CO}_{2}\) (b) \(\mathrm{CO}_{2}\) and \(\mathrm{NO}_{2}\) (c) \(\mathrm{SO}_{2}\) and \(\mathrm{NO}_{2}\) (d) \(\mathrm{SO}_{2}\) and \(\mathrm{O}_{3}\)

Which one of the following substances used in dry cleaning is a better strategy to control environmental pollution? (a) Sulphur dioxide (b) Carbon dioxide (c) Nitrogen dioxide (d) Tetrachloroethylene

Photochemical smog consists of excessive amount of \(\mathrm{X}\), in addition to aldehydes, ketones, peroxyacetyl nitrate (PAN), and so forth \(X\) is : (a) \(\mathrm{CO}\) (b) \(\mathrm{CH}_{4}\) (c) \(\mathrm{O}_{3}\) (d) \(\mathrm{CO}_{2}\)

Global warming is due to increase of: (a) methane and nitrous oxide in atmosphere (b) methane and \(\mathrm{CO}_{2}\) in atmosphere (c) methane and \(\mathrm{O}_{3}\) in atmosphere (d) methane and \(\mathrm{CO}\) in atmosphere

Which of the following statements about the depletion of ozone layer is correct? (a) The problem of ozone depletion is less serious at poles because \(\mathrm{NO}_{2}\) solidifies and is not available for consuming CIO' radicals. (b) The problem of ozone depletion is more serious at poles because ice crystals in the clouds over poles act as catalyst for photochemical reactions involving the decomposition of ozone of \(\mathrm{Cl}^{\circ}\) and \(\mathrm{CIO}^{\circ}\) radicals. (c) Freons, chlorofluorocarbons, are inert. Chemically, they do not react with ozone in stratosphere. (d) Oxides of nitrogen also do not react with ozone in stratosphere.

The gas leaked from a storage tank of the Union Carbide plant in Bhopal gas tragedy was : (a) Methyl isocyanate (b) Methylamine (c) Ammonia (d) Phosgene