Environmental Engineering In Ce — Part 1 MCQs with Explanations

The Threshold Limit Value (TLV) of aldrin in a public water supply system is about 17 μg/litre. This value represents the recommended maximum allowable concentration of aldrin in public water sources to ensure safety and minimize health risks. Aldrins are a group of organochlorine pesticides used in agriculture. They are known for their toxicity and persistence in the environment. To protect public health, regulatory authorities set limits on the concentration of these chemicals in drinking water. In this context: TLV stands for Threshold Limit Value, which is a term used to specify the maximum concentration of a substance that is considered safe to be present in a particular environment, in this case, public water supply systems. "μg/litre" indicates the unit of measurement, which is micrograms per liter. This is a very low concentration level, highlighting the need to maintain water quality. The TLV of 17 μg/litre for aldrin is a guideline to ensure that the concentration of aldrin in public water sources does not exceed this value to protect human health. It is essential to monitor and control the levels of aldrin and other harmful substances in drinking water to provide safe and clean water to the public.

A) Petroleum Refineries: Petroleum (crude oil) naturally contains sulfur compounds. During the refining process, these sulfur compounds are converted into hydrogen sulfide (H 2 S). Refineries then need to remove this H 2 S to produce cleaner fuels. This removal process, if not properly controlled, releases H 2 S into the air. Therefore, petroleum refineries are a significant and well-known source of H 2 S emissions. B) Coal-based Thermal Power Plants: Coal also contains sulfur, and burning it releases sulfur dioxide (SO 2 ), primarily, not H 2 S. While some very small amounts of H 2 S *might* be present, it's not the primary sulfur-containing air pollutant from coal power plants. C) Pulp and Paper Plants: These plants can release various sulfur compounds, including methyl mercaptan and dimethyl sulfide, especially during the pulping process. However, H 2 S isn't usually the *main* sulfur-containing air pollutant released, although it can be present in smaller quantities. D) Metallurgical Roasting & Smelting Plant: These processes deal with metal ores. If the ores contain sulfur, roasting and smelting primarily produce sulfur dioxide (SO 2 ). Again, while trace amounts of H 2 S could be formed, it's not the dominant sulfur emission. In summary: While all options *can* potentially release some H 2 S, petroleum refineries are the *major* industrial source because of the sulfur content inherent in crude oil and the H 2 S formation during refining.

75 is the correct answer to “Maximum permissible limit of industrial noise as recommended by World Health Organisation (WHO) is __________ decibels.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

Fluoride is the correct answer to “Fluorosis is caused due to the presence of excessive amount of __________ in drinking water.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

CO2 is the correct answer to “Smog is not formed due to the presence of __________ in the atmosphere.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

1 is the correct answer to “Dose of chlorine for disinfection of water is about __________ mg/litre of water.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

Nitric acid plant is the correct answer to “Which of the following plants does not emit appreciable amount of SO 2 in atmosphere”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

Discoloration of bathroom fixtures is the correct answer to “Presence of iron and manganese in water causes”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

Natural organic products is the correct answer to “What is the major constituents of waste/polluted water discharged from textile, pulp & paper, tanning, distillary, dairy and meat packing industries”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

Causes asphyxia is the correct answer to “Presence of carbon monoxide in atmosphere produced by decomposition of chlorophyl and haemoglobin breakdown of some animals, beyond TLV (> 50 ppm)”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

Ozone is the correct answer to “A considerable part of the harmful ultraviolet radiation of the sum does not reach the earth surface, because of the fact that, there is a layer of __________ high above earth's atmosphere, which absorbs it.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

Neutralised by alkali treatment is the correct answer to “Coal mines drainage waste water (acidic in nature) results from the earth's water percolating through the voids created in coal bed during mining. This polluted water which either drains out naturally to water courses or are removed before starting the mining is”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

3 is the correct answer to “Major sources of noise in furnace operation arises from air inspirators, combustion, side wall vibrations and fluctuation in the process heat load. A 50% increase in fuel firing rate may increase the furnace noise level by about __________ decibels.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

Cancer is the correct answer to “Exposure to chemicals having carcinogenic properties cause”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

700 ppm is the correct answer to “Beyond what concentration of H 2 S in air, acute danger to human life exists”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

Gravity separator having oil skimming devices is the correct answer to “The main pollutant in waste water discharged from a petroleum refinery is oil (both in free and emulsified form). Free oil is removed by”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

100 to 200 is the correct answer to “Water filtration rate in a slow sand filter ranges from __________ litres/m 2 /hr.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

CO, CO2 & SO2 is the correct answer to “Main pollutants released from iron & steel industry is”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

CH4 is the correct answer to “The principal gas evolved from sludge digestion tank is”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

'Green house' is colder than the outside atmosphere is the correct answer to “Pick out the wrong statement pertaining to 'green house' for the plants.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

Mud balls is the correct answer to “Insufficient washing of sand grains in a rapid sand filter causes”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

Cracking of rubber products is the correct answer to “Presence of high concentration of ozone and smog in atmospheric air causes the”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

Explosion is the correct answer to “Presence of volatile compounds like gasoline, oil, alcohol, ether etc. in municipal sewers may cause”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

Suspended inorganic matter is the correct answer to “Turbidity of water is an indication of the presence of”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

170 is the correct answer to “Noise level heard at a distance of about 100 metres from a jet engine with after burner is about __________ decibels.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

90 is the correct answer to “Maximum allowable noise exposure limits for a man working for 8 hours a day in a noisy chemical plant is about __________ decibels.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

90 is the correct answer to “The maximum permissible noise level to which a man working in a chemical plant can be exposed for eight hours per day is about __________ decibels.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

105 is the correct answer to “Noise emitted by a ventilation fan at a distance of 3 metres is about __________ decibels.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

100 is the correct answer to “Noise level inside a jet air liner in normal flight is about __________ decibels.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

50 is the correct answer to “Noise level in a quiet private business office is about __________ decibels.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

45 is the correct answer to “Noise level during normal conversation among men is about __________ decibles.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

EDTA is the correct answer to “A standard test for determination of hardness in water is termed as __________ test.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

Inorganic is the correct answer to “Waste/polluted water discharged from electroplating, blast furnace and coal mining industries contain mainly __________ substances.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

Phenol and cynide is the correct answer to “Which of the following is the most lethal water pollutant”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

Centrifugal force on is the correct answer to “Operating principle of cyclone separator is based on the action of __________ dust particles.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

Low amount of excess combustion air is the correct answer to “Black smoke coming out of the chimney of a furnace is an indication of the use of __________ in the furnace.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

80 is the correct answer to “Shouting by a man at his full voice corresponds to a voice level of about __________ decibels.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

90-120 is the correct answer to “COD of raw municipal sewage may be in the range of about __________ mg/litre.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

150-300 is the correct answer to “BOD of raw municipal sewage may be in the range of about __________ mg/litre.”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.

Troposphere is the correct answer to “The lowest layer of atmosphere is known as the”. This question is standard in competitive examination syllabi for Environmental Engineering In Ce.