Q. Removal of __________ results from the disinfection of water.

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Q. Very small amount of air pollutants are present in stratosphere also; though most of the atmospheric pollutants are present in the troposphere. Which of the following atmospheric pollutants does not cause the ozone layer depletion in atmosphere at tremendous rate ?

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Q. Carcinogenic air pollutants cause

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Q. Inhalation of silica dust by human being during hand drilling in mica mining, lead & zinc mining, silica refractory manufacture and in foundaries causes

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Q. Soluble silica present in boiler feed water can be removed by

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Q. The common pollutant generated in chlor-alkali industry and battery manufacture is

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Q. During sewage treatment, the sewage is subjected to __________ treatment in Imhoff tank.

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Q. Black smoke coming out of the chimney of a furnace is an indication of the use of __________ in the furnace.

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Q. Pick out the wrong statement.

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Q. __________ content of the phosphate rock is the pollutant of primary interest in a phos-phatic fertiliser plant.

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Q. 'Safe limit' called Threshold Limit Value (TLV) of carbon monoxide in atmospheric air is < 50 ppm. The main source of carbon monoxide pollutant in air is the

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Q. Inhalation of silica dust by human being causes

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Q. Which of the following air pollutants is not toxic to vegetation i.e., doesn't cause vegetation damage ?

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Q. A masonry structure built below ground level, where biochemical reaction takes place due to anaerobic bacteria is called

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Q. 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.

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Q. Insufficient washing of sand grains in a rapid sand filter causes

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Q. Which of the following sources is responsible for maximum air pollution ?

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Q. Which of the following is the most efficient for removal of very finely divided suspended solids and colloidal matter from the polluted water stream ?

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Q. In sewage treatment, its sedimentation is speeded up by commonly adding

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Q. Noise level in a quiet private business office is about __________ decibels.

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