Tag: environmental issues

Questions Related to environmental issues

Antinocking agent added to petrol is commonly

  1. Tetramethyl or tetraethyl lead

  2. Dibromoethane

  3. Both A and B

  4. Octane


Correct Option: C
Explanation:

Antiknocking agents are the chemical derivatives that are added to petrol. These agents increase the octane number of petrol due to which the pressure and temperature of petrol increases and so these protect petrol from detonation at low pressure. This is done to maintain the quality of the engines. Tetramethyl or tetraethyl lead, dibromoethane, benzole toluene are used as the antiknocking agents.

Hence, the correct answer is 'Both A and B'.

Antiknocking agent of unleaded petrol is

  1. Dibromomethane

  2. Methyl-ethyl ether

  3. Propane

  4. Methyl tert. butyl ether


Correct Option: D
Explanation:

Unleaded petrol is not doped with lead so it has a high knocking ability. It means it can be ignited before the actual ignition spark occurs. This is harmful to the engines. Lead is not used because it has shown severe adverse effects on the environment. Instead, methyl tertiary butyl ether is added which is easily miscible with petrol. However, it also has shown the carcinogenic properties.

Hence, the correct answer is 'Methyl tertiary butyl ether'.

Which one of the following will not control particulate pollutants?

  1. Incinerator

  2. Arrester

  3. Scrubber

  4. Filter

  5. Electrostatic precipitator


Correct Option: A
Explanation:

Incineration is also called as a thermal process, it involves combustion of organic substances contained in waste material. It converts the waste material into ash, gases, particles and heat which are then put into the application for generation of electricity. The incinerator is the device where waste is burnt e.g. furnace. Now incinerators are equipped with systems to reduce the emission of highly toxic gases during the process. The output of incinerator is gases, particles and heat thus for controlling particulate pollutant filtration and precipitators are installed to clean out the gases as a result of incineration. These do not have any control over particulate pollutants.

Hence the correct answer is 'Incinerator'.

Catalytic convertor brings about

  1. Complete oxidation of hydrocarbons

  2. Oxidation of carbon monoxide to carbon dioxide

  3. Reduction of nitrogen oxide to nitrogen

  4. All of the above


Correct Option: D
Explanation:
The catalytic converter is used to convert toxic and harmful pollutant into less toxic emission before they are released in the atmosphere from the engine of motor vehicles. The catalytic converter works as two types- reduction catalyst and the oxidation catalyst. The catalyst is a substance that causes or accelerates a chemical reaction without being unaffected. 
The catalytic converter reduces carbon monoxide hydrocarbon and nitrous oxides.
(A) The oxidation catalyst reduces the carbon monoxide by oxidizing by reacting carbon monoxide with oxygen in exhaust gas forming carbon dioxide.
(B) The oxidation catalyst burns the hydrocarbons and aids the reaction with leftover oxygen in the exhaust.
(C) The reduction catalyst separates nitrogen atom out of nitrous oxides and freezes oxygen, the nitrogen atom combines with another nitrogen atoms forming nitrogen.
Hence, the correct answer is 'All of the above'

Catalytic converter used for controlling pollution is used in

  1. Thermal plants

  2. Chimneys

  3. Brick kilns

  4. Motor vehicles


Correct Option: D
Explanation:
The catalytic converter is used to convert toxic and harmful pollutant into less toxic emission before they are released in the atmosphere from the engine of motor vehicles. The catalytic converter works as two types- reduction catalyst and the oxidation catalyst. The catalyst is a substance that causes or accelerates a chemical reaction without being unaffected. The catalytic converter reduces carbon monoxide hydrocarbon and nitrous oxides. The reduction catalyst separates nitrogen atom out of nitrous oxides and freezes oxygen, the nitrogen atom combines with another nitrogen atoms forming Nitrogen. The oxidation catalyst reduces the carbon monoxide by oxidizing by reacting carbon monoxide with oxygen in exhaust gas forming carbon dioxide.
Hence, the correct answer is 'Motor vehicles'.

Gaseous pollutants are controlled through

  1. Adsorption

  2. ESP

  3. Arrestors

  4. Pyrolysis

  5. Incineration


Correct Option: A
Explanation:

Gaseous pollutants include dust, aerosols, suspended particulate matter etc. that are removed by the principle of adsorption. Electrostatic precipitators, cyclones, scrubbers etc. are some devices that can control the gaseous pollutants. These are either made to be retained by the electrostatic field or by pressure. Pyrolisis and incineration are performed for solid pollutants. Arrestors are used to protect the types of equipment from the damaging effect of lightning.

Hence, the correct answer is 'Adsorption'.

Which one of the following is correct?

  1. Catalytic converter can precipitate particular matter of less than $2.5$ $\mu$m.

  2. Histones are acidic and form core of DNA packing.

  3. Template with $5'\rightarrow 3'$ polarity shows continuous DNA replication.

  4. Lactobacillus is not present in dough used for idli preparation.


Correct Option: D
Explanation:
Fermentation is required for the preparation of dough and for that, Yeast is used. Lactobacillus is used in the preparation of curd.
A. Catalytic converters primarily work by converting the toxic gases released from the vehicular exhausts into the non-toxic substances before they are released into the atmosphere. 
B. Histones are the basic or positively charged proteins made up of amino acids lysine and arginine. They perform packaging of DNA in eukaryotic cells.
C. DNA template with 5′→3′ polarity shows discontinuous replication via the formation of the Okazaki fragments. The 3′→5′ shows continuous replication.
D. Lactobacillus is the main agent that creates curd from milk. For making the dough, Yeast is used that makes the release of carbon dioxide by fermentation.
Hence, the correct answer is 'Lactobacillus is not present in dough used for idli preparation.'

Electrostatic precipitators (ESP) are used to control

  1. pesticide pollution

  2. air pollution

  3. radioactive pollution

  4. water pollution


Correct Option: B
Explanation:

Electrostatic precipitators (ESP)  is a device that removes suspended dust particles from a gas or exhaust by applying a high-voltage electrostatic charge and collecting the particles on charged plates. Electrostatic precipitator, also called electrostatic air cleaner, a device that uses an electric charge to remove certain impurities—either solid particles or liquid droplets—from the air or other gases.

So, the correct option is 'Air pollution'.

Pyrogallol is used in gas analysis because its

  1. Alkaline solution absorbs oxygen

  2. Acidic solution absorbs oxygen

  3. Alkaline solution reacts with carbon dioxide

  4. Acidic solution absorbs nitrogen


Correct Option: A
Explanation:

pyrogallol is also called as 1,2,3-trihydroxybenzene. It is a benzenetriol. It is a reducing agent. It is used as a developer in photography. It is also used as a coupling agent in printing. It undergoes rapid autooxidation in alkaline solution. Hence, its alkaline solution is used in the gas analysis because it absorbs oxygen. 

Thus, the correct answer is 'Alkaline solution absorbs oxygen'.

Which of the following is a land pollution?

  1. Soil erosion

  2. Accumulation of litter

  3. Humus formation and accumulation

  4. Accumulation of animal waste


Correct Option: A