Tag: air and water pollution control

Questions Related to air and water pollution control

Which of the following is a tropospheric gaseous pollutant?

  1. $H _2S$

  2. Dust

  3. Smoke

  4. Mist


Correct Option: A
Explanation:

Tropospheric pollution is caused by gaseous pollutant and particulate matter. Some of the gaseous air pollutant are hydrogen sulphide, oxides of sulphur, oxides of nitrogen etc.

Which of the following air pollutant has a smell of rotten egg?

  1. Hydrogen sulphide

  2. Hydrogen chloride

  3. Ammonia

  4. Nitric acid


Correct Option: A
Explanation:

Hydrogen sulfide gas is a naturally occuring chemical. The gas has a characteristic rotten egg odor at low concentrations. About half of the population can smell it at concentrations as low as 8 parts per billion (ppb) in air, and more than 90% can smell it at levels of 50 ppb.  At higher concentrations, hydrogen sulfide rapidly deadens the sense of smell.

Hydrocarbons is produced as a result of:

  1. fertilizer

  2. incomplete combustion of fuels in automobile engines.

  3. paper industry

  4. oil refinery


Correct Option: B
Explanation:

Hydrocarbon is produced as a result of incomplete combustion of fuels in automobile engines.
In animals, hydrocarbons can cause cancer, while in plants, they cause ageing by breaking down tissues, which causes shedding of leaves, twigs and flowers.

Which of the following condition is caused due to lead pollutant?

  1. Kidney damage

  2. Brain damage

  3. CNS damage

  4. All of above


Correct Option: D
Explanation:

Lead is one of the major pollutant which is released from lead batteries, industries etc. It damages kidney, liver, brain and central nervous system.

Oil or natural gas is considered sour if it has a high percentage of:

  1. hydrogen chloride

  2. sulphuric acid

  3. hydrogen sulphide

  4. chlorine


Correct Option: C
Explanation:

Hydrogen sulfide gas is found in petroleum and natural gas. Oil or natural gas is considered sour if it has a high percentage of hydrogen sulfide. Natural gas can contain up to 28 percent hydrogen sulfide gas, consequently,  it may be an air pollutant near petroleum refineries and in oil and gas extraction areas.

In the atmosphere, the presence of which can form a brown ring with $FeSO _{4}$?

  1. $NO$

  2. $N _{2}$

  3. $NO _{2}$

  4. $N _{2}O$


Correct Option: A
Explanation:

Brown ring compound $FeSO _4.NO$

What is the reason for irritant red haze in traffic and congested places?

  1. Oxides of nitrogen

  2. Oxides of sulphur

  3. Oxides of carbon

  4. Oxides of phosphorus


Correct Option: A
Explanation:
The irritant red haze in traffic and congested places is due to the oxides of Nitrogen.
Nitrogen dioxide has a deep red color ,and is a poisonous gas. When it is mixed with aerosols, it causes reddish brown colour of haze in congested places.The fuel release of cars and trucks are the major sources of Nitrogen oxides. Mostly NO is present in automobile exhaust, and ​once this NO is released in the atmosphere it combines with Oxygen of the air to form by the following chemical reaction.
                          $2NO+{ O } _{ 2 }\longrightarrow 2N{ O } _{ 2 }$

 Automobile emits which gases (in large quantities):


  1. $NO$ and $NO _2$

  2. $CO$ and $CO _2$

  3. $NO _2$

  4. $NO$ and $N _2O _5$


Correct Option: A
Explanation:

Air pollution from cars and trucks is split into primary and secondary pollution. Primary pollution is emitted directly into the atmosphere; secondary pollution results from chemical reactions between pollutants in the atmosphere. The following are the major pollutants from motor vehicles:

  1. Particulate matter (PM)
  2. Hydrocarbons (HC)
  3. Nitrogen oxides (NOX)
  4. Carbon monoxide (CO)
  5. Sulfur dioxide
  6. Hazardous air pollutants
  7. Greenhouse gases

Which of the following is precursors of photochemical smog?

  1. $NO _2$ and Hydrocarbon

  2. $P _2O _5$  and HydrocarbonP2O5

  3. Ethanol and $NO _2$

  4. Methanol and $SiO _2$


Correct Option: A
Explanation:
  1. Photochemical smog is composed of primary and secondary pollutants.
  2. Primary pollutants, which include nitrogen oxides and volatile organic compounds are introduced into the atmosphere via vehicular emissions and industrial processes.
  3. Secondary pollutants, like ozone, result from the reaction of primary pollutants with ultraviolet light.

From the followings, which is the correct statement?

  1. CO which is a major pollutant resulting from the combustion of fuels in automobiles plays a major role in photochemical smog

  2. Classical smog has a reducing character while photochemical smog has reducing character

  3. Classical smog has an oxidizing character while the photochemical smog is reducing in character

  4. During formation of smog, the level of ozone in the atmosphere goes down


Correct Option: C
Explanation:

Nowadays, the mixture of particulates with gaseous oxides of sulphur present in the atmosphere is called classical smog. The principal source of classical smog is the combustion of industrial and household fuels (coal and petroleum). Because of the presence of $S{ O } _{ 2 }$ and carbon (soot) particles, classical smog has a reducing character. It occurs in winter months, particularly in early morning hours. It causes severe lung and throat irritation.

The reaction of sunlight with hydrocarbons and ${ NO } _{ 2 }$ results in a variety of chemical products. One of these is ozone, made up of 3 atoms of oxygen, which is an irritating noxious gas. Other undesirable chemicals such as aldehydes also result from this photochemical reaction. This type of smog is oxidizing in character because of the presence of ozone, nitrogen dioxide, and some photochemical oxidants.