Description : Disposal to sewage in large cities, is done in A. Irrigation B. Dilution C. Oxidation D. Purification
Last Answer : ANS: B
Description : The factor responsible for purification of sewage in river is A. Hydrology B. Dissolved oxygen in water C. Temperature D. All the above
Last Answer : ANS: D
Description : 54 Pick up the correct statement from the following: A. The ratio of the quantity of the diluting water to that of the sewage, is known as dilution factor B. The automatic purification of polluted ... phenomenon C. The photosynthesis is carried out in the presence of sun light D. All the above
Description : In sewers the gas generally found, is A. Hydrogen sulphide (H2S) B. Carbon dioxide (CO2) C. Methane (CH4) D. All the above
Description : In a sludge tank, the gas mainly produced, is A. Oxygen B. Nitrogen C. Hydrogen D. Carbon dioxide
Description : In sewage having fully oxidised organic matter, the nitrogen exists in the form of A. Nitrites B. Nitrates C. Free ammonia D. Aluminoid nitrogen
Description : The presence of free ammonia in sewage, is detected by A. Boiling B. Adding potassium permanganate C. Adding sulphuric acid D. Phenol-di-sulphuric acid
Last Answer : ANS: A
Description : In very first stage of decomposition of the organic matter in sewage A. Nitrites are formed B. Nitrates are formed C. Carbondioxide is formed D. Ammonia is formed
Description : Nitrogen cycle of sewage, is A. Liberation of ammonia-formation of nitrites-formation of nitratesliberation of nitrogen B. Liberation of nitrogen-liberation of ammonia-formation of ... of ammonia D. Formation of nitrates-formation of nitrites-liberation of nitratesliberation of nitrates
Description : A well oxidized sewage contains nitrogen mainly as A. Nitrates B. Nitrites C. Free ammonia D. None of these
Description : Pick up the correct statement from the following: A. Hydrogen sulphide gas in excess, may cause corrosion of concrete sewers B. 4 ppm of Dissolved Oxygen (D.O.) is ensured before discharging the treated ... river C. Solubility of oxygen in sewage is 95% of that of distilled water D. All the above
Description : If a paper moistened with lead acetate for five minutes when placed in manhole turns black. The sewer certainly contains A. Hydrogen sulphide B. Carbon dioxide C. Methane D. Oxygen
Description : If the flame of a miner’s safety lamp in a manhole extinguishes within 5 minutes, the sewer certainly contains A. Hydrogen sulphide B. Carbon dioxide C. Methane D. Oxygen
Description : If the flame of a miner’s safety lamp in the upper layers of the sewer forms an explosive, the sewer certainly contains A. Hydrogen sulphide B. Carbon dioxide C. Methane D. Oxygen
Last Answer : ANS: C
Description : The gas which may cause explosion in sewers, is A. Carbondioxide B. Methane C. Ammonia D. Carbon monoxide
Description : Pick up the incorrect statement from the following: A. The mixture of water and waste products, is called sewage B. The treated sewage effluents, are generally used for irrigating the ... is called sewerage D. The old convergence system was definitely better than water carried sewerage system
Description : Oxidation process results in the formation of A. Carbon dioxide B. Nitrates C. Sulphates D. All the above
Description : Pick up the incorrect statement from the following: A. The process of decomposing the organic matter under controlled anaerobic conditions, is called sludge digestion B. Sludge digestion is carried ... contain 75% carbon dioxide D. The gases produced in sludge digestion process, contain 75% methane
Description : No treatment of the sewage is given if dilution factor is A. Less than 150 B. Between 150 to 200 C. Between 200 to 300 D. More than 500
Description : WASTE WATER ENGINEERING Objective Questions with Answers Q No: 161 The quantity of liquid waste which flows in sewers during the period of rainfall, is known A. Sanitary sewage B. Industrial waste C. Storm sewage D. None of these
Description : During preliminary treatment of a sewage A. Oil and grease are removed from skimming tanks B. Floating materials are removed by screening C. Girt and sand are removed by girt chambers D. All the above
Description : Tear gas used by the police to disperse the mob contains - (1) Carbon dioxide (2) Chlorine (3) Ammonia (4) Hydrogen sulphide
Last Answer : (2) Chlorine Explanation: Tear gas, formally known as a lachrymatory agent, is a possibly lethal chemical weapon that stimulates the corneal nerves in the eyes to cause tears, pain, and even blindness.
Description : Tear gas used by the police to disperse the mob contains – (1) carbon dioxide (2) chlorine (3) ammonia (4) hydrogen sulphide
Last Answer : (2) chlorine Explanation: Tear gas is a compound. Each molecule of tear gas contains one atom of chlorine. The compound 2- chlorobenzalmalononitrile, a cyanocarbon, is the defining component of a "tear gas" commonly referred to as CS gas, which is used as a riot control agent.
Description : The gas dissolved in water that makes it basic is : (1) ammonia (2) sulphur dioxide (3) hydrogen (4) carbon dioxide
Last Answer : ammonia
Description : Tear gas used by the police to disperse the mob contains (1) carbon dioxide (2) chlorine (3) ammonia (4) hydrogen sulphide
Last Answer : chlorine
Description : Before discharging the foul sewage into rivers, it is generally treated by A. Screening B. Sedimentation C. Oxidation D. All the above
Description : In 1000 kg of sewage, the total solids approximate A. 0.5 to 1.0 kg B. 1 kg to 2.0 kg C. 5 kg to 7.5 kg D. 7.5 kg to 10 kg
Description : Aerobic activity is maximum A. In freshly produced sewage B. At sewer pipes C. In sewer treatment plants D. None of these
Description : To test chemical oxygen demand (C.O.D.) of sewage, organic matter is oxidised by potassium dichromate in the presence of A. Hydrochloric acid B. Sulphuric acid C. Nitric acid D. Citric acid
Description : The sewer which transports the sewage to the point of treatment, is called A. House sewer B. Out-fall sewer C. Branch sewer D. Main sewer
Description : In sewage, the solids in mg per litre is A. 100 to 500 B. 500 to 1000 C. 1000 to 1500 D. 1500 to 2000
Description : The sewage discharge in a detritus tank of a treatment plant is 576 litres/sec with flow velocity of 0.2 m/sec. If the ratio of width to depth is 2, the depth is A. 100 cm B. 110 cm C. 120 cm D. 150 cm
Description : Fresh sewage may become stale in A. One hour B. Two to three hours C. Three to four hours D. Six hours
Description : Rate of flow of sewage is generally assumed A. More than the rate of water supply B. Equal to the rate of water supply C. Less than the rate of water supply D. At 150 litres per capita
Description : Removal of oil and grease from sewage, is known A. Screening B. Skimming C. Filtration D. None of these
Description : The ratio of minimum hourly flow to the average flow of sewage is A. 1/4 B. 1/3 C. 1/2 D. 3/4
Description : Q No: 291 The coagulant widely used for sewage treatment, is A. Alum B. Ferric chloride C. Ferric sulphate D. Chlorinated copperas
Description : The sewer pipe which carries sewage from a building for immediate disposal is A. House sewer B. Lateral sewer C. Intercepting sewer D. Main sewer
Description : When drainage to sewage ratio is 20, the peak dry weather flow is A. 20% of the design discharge B. Slightly less than 5% of the design discharge C. Slightly more than 5% of the design discharge D. None of these
Description : The non-clog pump which permits solid matter to pass out with the liquid sewage, is A. Centrifugal pump B. Reciprocating pump C. Pneumatic ejector D. None of these
Description : Q No: 271 Pick up the correct statement from the following: A. Turbidity is more in strong sewage B. The black colour indicates septic sewage C. The sewage omits offensive odours after four hours D. All the above
Description : The sewage is pumped up A. From low lying areas B. From flat areas C. From basements D. All the above
Description : Dry water flow in a combined sewer, is A. Industrial sewage B. Domestic sewage C. Storm water D. Inclusive of domestic and industrial sewage but excludes storm water
Description : 3.0 ml of raw sewage is diluted to 300 ml. The D.O. concentration of the diluted sample at the beginning of the test was 8 mg/l. After 5 dayincubation at 20°C, the D.O. concentration was 5 mg/l. The BOD of raw sewerage is A. 100 mg/l B. 200 mg/l C. 300 mg/l D. 400 mg/l
Description : The dimensions of a rectangular settling tank are: length 24 m, width 6 m and depth 3 m. If 2 hour detention period for tanks is recommended, the rate of flow of sewage per hour, is A. 204 cu.m B. 208 cu.m C. 212 cu.m D. 216 cu.m
Description : The sewage treatment in septic tanks is due to A. Anaerobic decomposition B. Aerobic decomposition C. Parasitic decomposition D. None of these
Description : A rain sanitary sewer is constructed to carry A. Sanitary sewage B. Storm sewage C. Surface water D. Ground water
Description : For detecting the nitrites in the sewage, the matching colour may be developed by adding A. Potassium permanganate B. Sulphuric acid and napthamine C. Phenol-di -sulphuric acid potassium hydroxide D. None of these
Description : Fresh sewage is generally A. Alkaline B. Acidic C. Highly decomposed D. A source of objectionable odour
Description : For sewer mains of 0.5 to 1 m diameter, the ratio of maximum daily sewage flow to the average daily sewage flow is assumed A. 1.5 B. 2.0 C. 2.5 D. 3.0