Description : The average temperature of sewage in India, is A. 10°C B. 15°C C. 20°C D. 25°C
Last Answer : ANS: C
Description : The Manufacturer of aeration devices reports the oxygen transfer rate of the device obtained through laboratory tests carried under standard conditions. Such standard condition are : (a) Wastewater at zero DO, 25°C and 760 mm ... DO, 20°C and 760 mm Hg (d) Wastewater at zero DO, 0°C and 700 mm Hg
Last Answer : (c) Tapwater at zero DO, 20°C and 760 mm Hg
Description : Normal temperature and pressure (N.T.P.) corresponds to (A) 0°C and 760 mm Hg (B) 15°C and 760 mm Hg (C) 20°C and 760 mm Hg (D) 0°C and 1 kgf/cm2
Last Answer : (C) 20°C and 760 mm Hg
Description : Which of the following are optimum temperature conditions for making benzenediazonium chloride from aniline? (a) 0°C to 10°C (b) 20°C to 25°C (c) 30°C to 40°C (d) 45°C to 50°C
Last Answer : 0°C to 10°C
Description : If the depletion of oxygen is found to be 2.5 mg/litre after incubating 2.5 ml of sewage diluted to 250 ml for 5 days at 20°C, B.O.D. of the sewage is A. 50 mg/l B. 100 mg/l C. 150 mg/l D. 250 mg/l
Last Answer : ANS: D
Description : If 2% solution of a sewage sample is incubated for 5 days at 20°C and depletion of oxygen was found to be 5 ppm, B.O.D. of the sewage is A. 200 ppm B. 225 ppm C. 250 ppm D. None of these
Description : If a 2% solution of sewage sample is incubated for 5 days at 20°C and the dissolved oxygen depletion was found to be 8 mg/l. The BOD of the sewage is A. 100 mg/l B. 200 mg/l C. 300 mg/l D. 400 mg/l
Description : A five day B.O.D. at 15°C of the sewage of a town is 100 kg/day. If the 5 day B.O.D. per head at 15°C for standard sewage is 0.1 kg/day, the population equivalent is A. 100 B. 1000 C. 5000 D. 10000
Description : Standard air is the: a. Mass of 1 cubic meter of dry air at 20°C and atmospheric pressure b. Mass of a cubic meter of air at atmospheric conditions c. Volume of air at ambient temperature and atmospheric pressure ... pressure at sea level or 101.325 kPa e. Volume of 1 kg of air at 15°C and 100 kPa
Last Answer : Answer: D
Description : Optimum temperature for maximum crop development in wheat is (a) 10-15°C(b) 20-25°C (c) 25-30°C (d) 30-35°C
Last Answer : (b) 20-25°C
Description : Bio-chemical oxygen demand (BOD) for the first 20 days in generally referred to A. Initial demand B. First stage demand C. Carbonaceous demand D. All of these
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 temperature of the top of a frozen lake is – 15°C. What is the temperature of the water in the lake in contact with the ice layer? (a) 0°C (b) 4°C (c) –15°C (d) –7.5°C
Last Answer : Ans:(a)
Description : Temperature and gage pressure maintained during the manufacture of cold SBR (styrene butadiene rubber) are (A) 5°C and 1 kgf/cm2 (B) - 20°C and 1 kgf/cm2 (C) 0°C and 1 kgf/cm2 (D) 0°C and 3 kgf/cm
Last Answer : (A) 5°C and 1 kgf/cm
Description : Date growth does not cease if temperature does not fall below: a. 0°C. b. 10°C c. 18°C d. 20°C
Last Answer : 18°C
Description : If a certain amount of dry ice is mixed with same amount of water at 80°C, the final temperature of mixture will be (a) 80°C (b) 0°C (c) 40°C (d) 20°C (e) 60°C.
Last Answer : Answer : b
Description : The temperature condition for storage of drug products under cold temperature is given as : (A) temperature between 8°C and 25°C (B) temperature below 20 C (C) temperature at 0°C (D) temperature between 2c C and S: C
Last Answer : (D) temperature between 2c C and S: C
Description : A mixture of 10% C6H6 vapour in air at 25°C and 750 mm Hg has a dew point of 20°C. Its dew point at 30°C and 700 mm Hg will be around __________ °C. (A) 21.7 (B) 20 (C) 27.3 (D) 18.7
Last Answer : (D) 18.7
Description : The optimum cardinal temparature point for germination of rice seeds is– 1) 20°C – 25°C 2) 18°C – 22°C 3) 30°C – 32°C 4) 37°C – 39°C
Last Answer : 1) 20°C – 25°C
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
Last Answer : ANS: B
Description : The amount of oxygen consumed by the aerobic bacterias which cause the aerobic biological decomposition of sewage, is known A. Bio-Chemical Oxygen Demand (B.O.D.) B. Dissolved Oxygen (D.O.) C. Chemical Oxygen Demand (C.O.D.) D. None of these
Description : The standard B.O.D. of water is taken for A. 1 day B. 2 days C. 3 days D. 5 days
Description : If the depletion of oxygen is found to be 5 ppm after incubating a 2.5% solution of sewage sample for 5 days at 21°C, B.O.D. of the sewage is A. 50 ppm B. 100 ppm C. 150 ppm D. 200 ppm
Description : The bacteria which are able to grow at 0°C but which grow at 20°C to 30°C, are known as a. Psychrophiles b. Facultative psychrophiles c. Average psychrophiles d. Mesophiles
Last Answer : Ans: C
Description : The density of water is 1 g/cc. This is strictly valid at – (1) 0°C (2) 4°C (3) 25°C (4) 100°C
Last Answer : (2) 4°C Explanation: Water never has an absolute density because its density varies with temperature. Water has its maximum density of 1 g/cm3 at 4 degrees Celsius. When the temperature changes from either greater or ... 1 g/cm3. Water has the maximum density of 1 g/cm3 only when it is pure water.
Description : The density of water is 1 g/cc. This is strictly valid at (1) 0°C (2) 4°C (3) 25°C (4) 100°C
Last Answer : 4°C
Description : (2) amount of oxygen used for biochemical oxidation Explanation: Biochemical oxygen demand or B.O.D. is the amount of dissolved oxygen needed by aerobic biological organisms in a body of water to ... quantitative test, although it is widely used as an indication of the organic quality of water.
Last Answer : The addition of gypsum to port-land cement helps in : (1) increasing the strength of cement (2) rapid setting of cement (3) preventing rapid setting of cement (4) reduction in the cost of cement
Description : The factor responsible for purification of sewage in river is A. Hydrology B. Dissolved oxygen in water C. Temperature D. All the above
Description : 11. Acid regression stage of sludge digestion at a temperature 21°C extends over a period of A. 15 days B. 30 days C. 60 days D. 90 days
Description : The standard B.O.D. at 20°C, is taken for the consumption in (A) 2 days (B) 3 days (C) 4 days (D) 5 days
Last Answer : (D) 5 days
Description : Biochemical Oxygen Demand (B.O.D.) of safe drinking water must be (A) Nil (B) 5 (C) 10 (D) 15
Last Answer : (A) Nil
Description : Biochemical Oxygen Demand (BOD) may not be a good index for pollution for water bodies receving effluents from:
Last Answer : Biochemical Oxygen Demand (BOD) may not be a good index for pollution for water bodies receving ... sewage C. Dairy industry D. Petroleum industry
Description : Biochemical oxygen demand measures:
Last Answer : Biochemical oxygen demand measures: A. Industrial pollution B. Air pollution C. Dissolved ... for decomposers D. Pollution capacity of effluents
Description : High value of BOD (Biochemical Oxygen Demand) indicates that:
Last Answer : High value of BOD (Biochemical Oxygen Demand) indicates that: A. Highly polluted water B. Less ... in water C. Less sewage D. Less microorganisms.
Last Answer : High value of BOD (Biochemical Oxygen Demand) indicates that: A. consumption of organic matter in ... is highly polluted D. water is less polluted
Description : Measuring Biochemical Oxygen Demand (BOD) is a method used for:
Last Answer : Measuring Biochemical Oxygen Demand (BOD) is a method used for: A. Measuring the activity of ... out the efficiency of oil driven automobile engines
Description : Biochemical oxygen demand (BOD) in a river water
Last Answer : Biochemical oxygen demand (BOD) in a river water A. Increases when sewage gets mixed with river ... water D. Gives a measure of Salmonella in water
Description : BOD stands for : (1) Biological oxidation demand (2) Biological oxygen demand (3) Biochemical oxygen demand (4) Biotic oxidation demand
Last Answer : (3) Biochemical oxygen demand Explanation: BOD stands for Biochemical Oxygen Demand. It is the amount of dissolved oxygen needed by aerobic biological organisms to break down organic material present in a ... in milligrams of oxygen consumed per litre of sample during 5 days of incubation at 20°C.
Description : Biochemical oxygen demand (BOD) in a river water (a) has no relationship with concentration of oxygen in the water (b) gives a measure of Salmonella in the water (c) increases when sewage gets mixed with river water (d) remains unchanged when algal bloom occurs.
Last Answer : (c) increases when sewage gets mixed with river water
Description : Measuring Biochemical Oxygen Demand (BOD) is a method used for (a) estimating the amount of organic matter in sewage water (b) working out the efficiency of oil driven automobile engines ... commercial scale (d) working out the efficiency of RBCs about their capacity to carry oxygen.
Last Answer : (a) estimating the amount of organic matter in sewage water
Description : High value of BOD (Biochemical Oxygen Demand) indicates that (a) water is less polluted (b) consumption of organic matter in the water is higher by the microbes (c) water is pure (d) water is highly polluted.
Last Answer : (b) consumption of organic matter in the water is
Description : Biochemical Oxygen Demand (BOD) may not be a good index for pollution for water bodies receiving effluents from (a) domestic sewage (b) dairy industry (c) petroleum industry (d) sugar industry.
Last Answer : c) petroleum industry
Description : Measuring Biochemical Oxygen Demand (BOD) is a method used for (a) estimating the amount of organic matter in sewage water (b) working out the efficiency of oil driven automobile engines (c) ... a commercial scale (d) working out the efficiency of RBCs about their capacity to carry oxygen.
Last Answer : (b) consumption of organic matter in the water is higher by the microbes
Last Answer : (c) petroleum industry
Description : Biochemical Oxygen Demand (BOD) of sewage is the (a) Oxygen required to oxidise (b) Oxygen required to oxidise biologically inactive organic matter* (c) a and b both (d) none of these
Last Answer : (b) Oxygen required to oxidise biologically inactive organic matter*
Description : 72. Measuring Biochemical Oxygen Demand (BOD) is a method used for (1) Working out the efficiency of R.B.Cs. about their capacity to carry oxygen (2) Estimating the amount of ... driven automobile engines (4) Measuring the activity of Sacccharomyces cerevisae in producing curd on a commercial scale
Last Answer : Estimating the amount of organic matter is sewage water
Last Answer : Biochemical oxygen demand
Description : It is customary to design a sewer for D.W.F. on the basis of A. Average demand B. Twice the average demand C. Thrice the average demand D. Four times the average demand