Pick out the wrong statement.
(A) Biological oxygen demand (BOD) is a characteristic and not a
constituent of water
(B) BOD is a measure of the amount of oxygen which will be demanded &
used in 5 days by the biological decomposition of the organic matter present in
water stream present as food for the living organism
(C) BOD is expressed in mg/litre (typically, BOD=2.5 mg/litre for potable
water)
(D) None of these

1 Answer

Answer :

(D) None of these

Related questions

Description : Pick out the correct statement. (A) Chemical oxygen demand (COD) is a measure of chemically oxidisable organic matter present in water (B) COD is determined by oxidising the organic matter present in water with potassium dichromate ... of potable water may be 1-2 mg/litre (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Description : The term Biological Oxygen Demand (BOD) is used in relation to (A) Potable water (B) Cooling water (C) Distilled water (D) Industrial effluents

Last Answer : (D) Industrial effluents

Description : Biological Oxygen Demand (BOD) is a measure of: a. Industrial wastes poured into water bodies b. Extent to which water is polluted with organic compounds c. Amount of carbon monoxide inseparably combined with haemoglobin d. Amount of oxygen needed by green plants during night

Last Answer : Ans: A

Description : Lagoons used for purification of polluted water (A) Are large shallow artificial lakes also known as clarification lakes, maturation ponds or oxidation ponds (B) Use micro-organisms/bacteria in presence of dissolved oxygen (C) Gives an ... 1 mg/litre and BOD = 3.8 mg/litre (D) All (A), (B) & (C)

Last Answer : (D) All (A), (B) & (C)

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 : 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 : (a) estimating the amount of organic matter in sewage water

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

Description : Which is the best and the most effective method for the removal of organic contaminant present in the polluted water in very small quantity (say < 200 mg/litre)? (A) Lagooning (B) Activated carbon adsorption (C) Biological oxidation pond (D) Chemical coagulation

Last Answer : (B) Activated carbon adsorption

Description : Pick out the wrong statement. (A) Biological oxygen demand (B.O.D.) value of a sewerage sample is always lower than its chemical oxygen demand (C.O.D.) value (B) Environmental pollution by ... in but does not allow the short wavelength infra red radiation to escape out of the earth's atmosphere

Last Answer : (D) The characteristic of a green house body is that it allows the long wavelength incoming solar radiation to come in but does not allow the short wavelength infra red radiation to escape out of the earth's atmosphere

Description : Biological oxygen demand (BOD) is a measure of

Last Answer : Biological oxygen demand (BOD) is a measure of A. Industrial wastes poured into water bodies ... Amount of oxygen needed by green plants during night

Description : Phenolic water generated in coke ovens & by-product plant attached to an integrated steel plant containing phenol in concentration of less than 100 mg/litre can be removed by (A) Chlorination (B) Treating in biological oxygen pond (C) Chemical coagulation (D) None of these

Last Answer : (B) Treating in biological oxygen pond

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 : 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 higher by the microbes

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 : (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 : BOD of raw municipal sewage may be in the range of about __________ mg/litre. (A) 1-2 (B) 5-10 (C) 150-300 (D) 2000-3000

Last Answer : (C) 150-300

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

Last Answer : ANS: B

Description : Consider the following statements : Activated sludge process can be said to comprise : 1. Conversion of dissolved organic matter into biological flocs 2. Removal of dissolved BOD of the waste water 3. Digestion of the sludge Which ... 2 and 3 (b) 1 and 2 only (c) 2 and 3 only (d) 1 and 3 only

Last Answer : (b) 1 and 2 only

Description : Assertion: Amount of biodegradable organic matter present in water is measured by BOD of water Reason: During biodegradation of organic compounds. Oxy

Last Answer : Assertion: Amount of biodegradable organic matter present in water is measured by BOD of water Reason: ... but reason is wrong D. both are wrong

Description : Pick out the wrong statement (A) Low ozone layer thickness in polar regions is due to cold climatic conditions (B) Amount of unburnt hydrocarbons emitted by two stroke petrol engine is more ... can enter the blood stream & the digestive system/ lungs and is responsible for causing Minamata disease

Last Answer : (D) Mercury as a pollutant can enter the blood stream & the digestive system/ lungs and is responsible for causing Minamata disease

Description : The ratio of oxygen available to the oxygen required for stabilisation of sewage is called the (A) Bacterial stability factor (B) Relative stability (C) Biological oxygen demand (BOD) (D) Oxygen ion concentration

Last Answer : (B) Relative stability

Description : Use of chlorine in the treatment of sewage (A) Helps in grease separation (B) Increases the biological oxygen demand (BOD) (C) Causes bulking of activated sludge (D) Aids in flocculation

Last Answer : (A) Helps in grease separation

Description : Water pollution can be identified by testing its A. PH level B. Biological Oxygen Demand (BOD) C. Both (a) and (b) D. None of these.

Last Answer : C. Both (a) and (b)

Description : Water pollution can be identified by testing its A. PH level B. Biological Oxygen Demand (BOD) C. Both (a) and (b) D. None of these.

Last Answer : C. Both (a) and (b)

Description : Eutrophication of a water body enhances – (1) Organic matter production (2) Biological oxygen demand (3) Both (1) and (2) (4) Neither (1) nor (2)

Last Answer : (3) Both (1) and (2) Explanation: Eutrophication is the ecosystem response to the addition of artificial or natural substances, such as nitrates and phosphates, through fertilizers or sew-age. It leads not only to increased levels of nutrients, but increased Biological Oxygen Demand as well.

Description : Eutrophication of a water body enhances (1) Organic matter production (2) Biological oxygen demand (3) Both (1) and (2) (4) Neither (1) nor (2)

Last Answer :  Both (1) and (2) 

Description : BOD (biological oxygen demand) is

Last Answer : BOD (biological oxygen demand) is A. Amount of oxygen consumed by microorganisms for decaying organic ... plants for survival D. None of the above

Description : Drained sewage has biological oxygen demand `(BOD)`:

Last Answer : Drained sewage has biological oxygen demand `(BOD)`: A. More than that of water B. Less than that of ... equal to that of water D. None of the above

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 : ater pollution can be identified by testing its A. PH level B. Biological Oxygen Demand (BOD) C. Both (a) and (b) D. None of these.

Last Answer : C. Both (a) and (b)

Description : BOD stands for : (1) Biological oxidation demand (2) Biological oxygen demand (3) Biochemical oxygen demand (4) Biotic oxidation demand

Last Answer : Biochemical oxygen demand

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

Last Answer : ANS: D

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 : 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 : The BOD values of water indicate the (1) amount of organic debris (2) amount of oxygen used for biochemical oxidation (3) amount of oxygen used for biochemical reduction (4) amount of ozone used for biochemical oxidation

Last Answer : amount of oxygen used for biochemical oxidation

Description : The detrimental effect on organism and water quality with temperature rise of aquatic system is the reduction of __________ of water. (A) Dissolved oxygen content (B) Biological oxygen demand (C) Vapor pressure (D) All (A), (B) and (C)

Last Answer : (A) Dissolved oxygen content

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

Last Answer : ANS: D

Description : Radioactive substances present in the polluted water stream can be removed by (A) Biological oxygen treatment (B) Coagulation and filtration (C) Adsorption in ion exchange materials (D) None of these

Last Answer : (C) Adsorption in ion exchange materials

Description : The biological decomposition of organic substances in wastes controlled conditions is called (A) Incineration (B) Biological oxidation (C) Composting (D) None of these

Last Answer : (C) Composting

Description : A hydrometer is used to measure the ____________. A. specific gravity of a battery electrolyte B. water pressure in a deck pipeline C. amount of potable water a vessel is taking on D. power developed by a salt water service pump

Last Answer : Answer: A

Description : Write a note on Biological Oxygen Demands (BOD) 

Last Answer : It is a measure of water pollution level due to sewage and other organic matter. Biological oxygen demands {BOD} is the amount of oxygen needed by microbs to decompose the organic matters of water in ... amount of sewage waste in water create at high BOD, which robs the water of dissolved oxygen.  

Description : Pick out the wrong statement: (A) Greater is the kinematic viscosity of the liquid, greater is the thickness of the boundary layer (B) Blowers develop a maximum pressure of 2 atmospheres ( ... factor in case of turbulent flow of liquids in pipe depends upon relative roughness & Reynolds number

Last Answer : (C) Friction losses in pipe fittings are generally expressed in terms of velocity heads

Description : Pick out the wrong statement. (A) Aromatics have higher specific gravity than paraffins (B) Gross calorific value (GCV) of petrofuels is equal to (12400 - 2100 ρ 2 ) where, ρ is the specific gravity ... volume basis (i.e., Kcal/litre) (D) Higher specific gravity of petrofuels means higher C/H ratio

Last Answer : (C) Heavier petrofuels have higher GCV on weight basis (i.e., Kcal/kg) but lower GCV on volume basis (i.e., Kcal/litre)

Description : The biological decomposition of organic substances in wastes under controlled conditions known as - (1) composting (2) incineration (3) sanitary landfill (4) pyrolysis

Last Answer : (1) composting

Description : The biological decomposition of organic substances in wastes under controlled conditions known as (1) composting (2) incineration (3) sanitary landfill (4) pyrolysis

Last Answer : composting

Description : Assertion : BOD of river polluted by sewage is more than 20 ppm. Reason: Polluted river contains excess of organic matter.

Last Answer : Assertion : BOD of river polluted by sewage is more than 20 ppm. Reason: Polluted river contains excess ... true but reason is wrong D. Both are wrong

Description : BOD is connected with a) Organic matter b) microbes c) Microbes and Organic matter d) None of the above.

Last Answer : c) Microbes and Organic matter

Description : Enzymes, vitamins and hormones can be classified into a single category of biological chemicals, because all of these (a) help in regulating metabolism (b) are exclusively synthesized in the body of a living organism as at present (c) are conjugated proteins (d) enhance oxidative metabolism.

Last Answer : (a) help in regulating metabolism

Description : Price elasticity of demand provides A.A measure of the responsiveness of the quantity demanded to changes in the price of the product, holding constant the values of all other variables in the demand function ... the firm C.A technical change in the cost of product D.Technical change in the value.

Last Answer : A.A measure of the responsiveness of the quantity demanded to changes in the price of the product, holding constant the values of all other variables in the demand function.

Description : Pick out the wrong statement. (A) High concentration of oxygen in flue gas means high stack loss (B) Gaseous fuels require the least % excess air for complete combustion (C) The ratio of fixed carbon to ... coal is called its 'fuel ratio' (D) Calorific value of natural gas is more than that of LPG

Last Answer : (D) Calorific value of natural gas is more than that of LPG