Presence of carbonaceous matter in the sewage (A) Causes reduction in its dissolved oxygen content thereby endangering the life of aquatic creatures (B) Reduces sulphate ions to sulphides causing obnoxious smell (C) Increases the quantity of chlorine used for its purification (D) All (A), (B) and (C)

Presence of carbonaceous matter in the sewage

(A) Causes reduction in its dissolved oxygen content thereby endangering

the life of aquatic creatures

(B) Reduces sulphate ions to sulphides causing obnoxious smell

(C) Increases the quantity of chlorine used for its purification

(D) All (A), (B) and (C)

by

1 Answer

Answer :

(D) All (A), (B) and (C)
by

Related questions

Presence of nitrogen in high concentration in contaminated air reduces partial pressure of oxygen in lungs, thereby causing asphyxia (suffocation) leading to death from oxygen deficiency. Concentration of N2 in contaminated air at which it acts as a natural asphyxiate is ≥ __________ percent. (A) 84 (B) 88 (C) 80 (D) 92

Description : Presence of nitrogen in high concentration in contaminated air reduces partial pressure of oxygen in lungs, thereby causing asphyxia (suffocation) leading to death from oxygen deficiency. Concentration of N2 in contaminated air at ... asphyxiate is ≥ __________ percent. (A) 84 (B) 88 (C) 80 (D) 92

Last Answer : (A) 84

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)

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

. Presence of iron and manganese in water causes (A) Reduction in its dissolved oxygen content (B) Discoloration of bathroom fixtures (C) Temporary hardness (D) None of these

Description : . Presence of iron and manganese in water causes (A) Reduction in its dissolved oxygen content (B) Discoloration of bathroom fixtures (C) Temporary hardness (D) None of these

Last Answer : (B) Discoloration of bathroom fixtures

The factor responsible for purification of sewage in river is A. Hydrology B. Dissolved oxygen in water C. Temperature D. All the above

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

What purpose does FeCl3 serve in the electrophilic aromatic substitution reaction between chlorine and benzene? (a) It serves as a radical initiator to produce the chlorine radical needed to propagate the chain reaction. (b) It functions by destabilizing the carbocationic intermediate and thereby increases the rate of H+ loss. (c) It serves as a Lewis base catalyst by reacting with Cl2 to generate chloride ions. (d) It serves as a Lewis acid catalyst by reacting with the Cl2 and thereby activates it toward attack by benzene’s π electrons.

Description : What purpose does FeCl3 serve in the electrophilic aromatic substitution reaction between chlorine and benzene? (a) It serves as a radical initiator to produce the chlorine radical needed to propagate the ... by reacting with the Cl2 and thereby activates it toward attack by benzene's π electrons.

Last Answer : It serves as a Lewis acid catalyst by reacting with the Cl2 and thereby activates it toward attack by benzene’s π electrons.

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 water, is known self purification phenomenon C. The photosynthesis is carried out in the presence of sun light D. All the above

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

Last Answer : ANS: D

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 excellent final effluent (with 3 to 4 lagoons arranged in series) having suspended solid < 1 mg/litre and BOD = 3.8 mg/litre (D) All (A), (B) & (C)

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)

For existence of aquatic life in water, the dissolved oxygen content in it, should not be less than __________ ppm. (A) 10000 (B) 5 (C) 500 (D) 1000

Description : For existence of aquatic life in water, the dissolved oxygen content in it, should not be less than __________ ppm. (A) 10000 (B) 5 (C) 500 (D) 1000

Last Answer : (B) 5

Sunlight (A) Helps growth of bacterias (B) Impedes growth of algae (C) Increases dissolved oxygen content (D) Reduces turb

Description : Sunlight  (A) Helps growth of bacterias  (B) Impedes growth of algae  (C) Increases dissolved oxygen content  (D) Reduces turb

Last Answer : (B) Impedes growth of algae

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

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

Bacterial aerobic oxidation of polluted water in biological oxidation ponds is done to purify it. Presence of bacteria helps in (A) Coagulation and flocculation of colloids (B) Oxidation of carbonaceous matter to CO2 (C) Nitrification or oxidation of ammonia derived from breakdown of nitrogenous organic matter to the nitrite and eventually to the nitrate (D) All (A), (B) and (C)

Description : Bacterial aerobic oxidation of polluted water in biological oxidation ponds is done to purify it. Presence of bacteria helps in (A) Coagulation and flocculation of colloids (B) Oxidation of carbonaceous matter to CO2 (C) ... to the nitrite and eventually to the nitrate (D) All (A), (B) and (C)

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

Lead pipes are not safe for carrying drinking water because water containing dissolved oxygen attacks lead thereby forming poisonous Pb (OH)2 . Lead pipes are readily corroded by (A) Dilute HCI (B) Acetic acid (C) Concentrated H2SO4 (D) None of these

Description : Lead pipes are not safe for carrying drinking water because water containing dissolved oxygen attacks lead thereby forming poisonous Pb (OH)2 . Lead pipes are readily corroded by (A) Dilute HCI (B) Acetic acid (C) Concentrated H2SO4 (D) None of these

Last Answer : (B) Acetic acid

Lead pipes are not safe for carrying drinking water, because water, containing dissolved oxygen attacks lead thereby forming poisonous Pb(OH)2 . Lead pipes are readily corroded by (A) Dilute HCl (B) Acetic acid (C) Concentrated H2SO4 (D) None of these

Description : Lead pipes are not safe for carrying drinking water, because water, containing dissolved oxygen attacks lead thereby forming poisonous Pb(OH)2 . Lead pipes are readily corroded by (A) Dilute HCl (B) Acetic acid (C) Concentrated H2SO4 (D) None of these

Last Answer : (B) Acetic acid

Dilution method of disposing of sewage, is not preferred to A. When sewage is fresh B. When diluting water has high dissolved oxygen content C. When diluting water is used for water supply near the point of sewage disposed D. When the diluting water is having flow currents

Description : Dilution method of disposing of sewage, is not preferred to A. When sewage is fresh B. When diluting water has high dissolved oxygen content C. When diluting water is used for water supply near the point of sewage disposed D. When the diluting water is having flow currents

Last Answer : ANS: C

High sulphur content in a fuel __________ of the flue gases. (A) Decreases the dew point (B) Increases the dew point (C) Reduces the combustion efficiency by limiting the permissible temperature reduction (D) Both (B) and (C)

Description : High sulphur content in a fuel __________ of the flue gases. (A) Decreases the dew point (B) Increases the dew point (C) Reduces the combustion efficiency by limiting the permissible temperature reduction (D) Both (B) and (C)

Last Answer : (D) Both (B) and (C)

Which of the following is an yellow pigment? (A) Titanium dioxide (B) Ferrous sulphate (C) Lead chromates (D) Zinc sulphides

Description : Which of the following is an yellow pigment? (A) Titanium dioxide (B) Ferrous sulphate (C) Lead chromates (D) Zinc sulphides

Last Answer : (C) Lead chromates

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 : 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

The Brake Horse power of the motor (efficiency 60%) required for a pump of capacity 0.075 cumec for a total lift of 12 m, is A. 10 B. 15 C. 20 D. 25 Q No: 44 Aerobic bacterias A. Flourish in the presence of free oxygen B. Consume organic matter as their food C. Oxidise organic matter in sewage D. All the above

Description : The Brake Horse power of the motor (efficiency 60%) required for a pump of capacity 0.075 cumec for a total lift of 12 m, is A. 10 B. 15 C. 20 D. 25 Q No: 44 Aerobic bacterias A. ... presence of free oxygen B. Consume organic matter as their food C. Oxidise organic matter in sewage D. All the above

Last Answer : ANS: D

Presence of non-biodegradable substances, like alkyl benzene sulphonate (ABS) from the detergents in polluted water stream causes (A) Fire hazards (B) Explosion hazards (C) Persistent foam (D) Depletion of dissolved oxygen

Description : Presence of non-biodegradable substances, like alkyl benzene sulphonate (ABS) from the detergents in polluted water stream causes (A) Fire hazards (B) Explosion hazards (C) Persistent foam (D) Depletion of dissolved oxygen

Last Answer : (C) Persistent foam

The nurse teaches the patient with peripheral vascular disease to refrain from smoking because nicotine causes a) vasospasm. Nicotine causes vasospasm and can thereby dramatically reduce circulation to the extremities. b) slowed heart rate. Nicotine has stimulant effects. c) depression of the cough reflex. Nicotine does not suppress cough. Smoking irritates the bronchial tree, causing coughing. d) diuresis. Nicotine does not cause diuresis.

Description : The nurse teaches the patient with peripheral vascular disease to refrain from smoking because nicotine causes a) vasospasm. Nicotine causes vasospasm and can thereby dramatically reduce circulation to the ... the bronchial tree, causing coughing. d) diuresis. Nicotine does not cause diuresis.

Last Answer : a) vasospasm. Nicotine causes vasospasm and can thereby dramatically reduce circulation to the extremities.

Presence of carbon monoxide in atmosphere produced by decomposition of chlorophyll and haemoglobin breakdown of some animals, beyond TLV (>50 ppm) (A) Acts as a green house gas thereby raising earth's temperature (B) Causes asphyxia (C) Causes increase in sea level (D) Enhances the green house effect

Description : Presence of carbon monoxide in atmosphere produced by decomposition of chlorophyll and haemoglobin breakdown of some animals, beyond TLV (>50 ppm) (A) Acts as a green house gas thereby raising earth's ... (B) Causes asphyxia (C) Causes increase in sea level (D) Enhances the green house effect

Last Answer : (B) Causes asphyxia

The optimum dissolved oxygen level (in mg/litre) required for survival of aquatic organisms is - (1) 4 - 6 (2) 2 - 4 (3) 8 - 10 (4) 12 - 16

Description : The optimum dissolved oxygen level (in mg/litre) required for survival of aquatic organisms is - (1) 4 - 6 (2) 2 - 4 (3) 8 - 10 (4) 12 - 16

Last Answer : (1) 4 - 6 Explanation: Oxygen is one of several dissolved gases important to aquatic systems. Dissolved oxygen is necessary to maintain aerobic conditions in surface waters and is ... approach saturation - that concentration which is in equilibrium with the partial pressure of atmospheric oxygen.

The optimum dissolved oxygen level (in mg/litre) required for survival of aquatic organisms is : (1) 4 – 6 (2) 2 – 4 (3) 8 – 10 (4) 12 – 16

Description : The optimum dissolved oxygen level (in mg/litre) required for survival of aquatic organisms is : (1) 4 – 6 (2) 2 – 4 (3) 8 – 10 (4) 12 – 16

Last Answer :  4 – 6

A river with an inflow of domestic sewage rich in organic waste may result in (a) an increased production of fish due to biodegradable nutrients (b) death of fish due to lack of oxygen (c) drying of the river very soon due to algal bloom (d) increased population of aquatic food web organisms.

Description : A river with an inflow of domestic sewage rich in  organic waste may result in  (a) an increased production of fish due to  biodegradable nutrients (b) death of fish due to lack of oxygen ( ... of the river very soon due to algal bloom (d) increased population of aquatic food web  organisms.

Last Answer : (d) increased population of aquatic food web  organisms.

A river with an inflow of domestic sewage rich in organic waste may result in (a) an increased production of fish due to biodegradable nutrients (b) death of fish due to lack of oxygen (c) drying of the river very soon due to algal bloom (d) increased population of aquatic food web organisms.

Description : A river with an inflow of domestic sewage rich in organic waste may result in (a) an increased production of fish due to biodegradable nutrients (b) death of fish due to lack of oxygen (c) drying of the river very soon due to algal bloom (d) increased population of aquatic food web organisms.

Last Answer : (b) death of fish due to lack of oxygen

Chlorine gas is produced by the electrolysis of brine (NaCl solution with solid NaCl make up) in mercury electrolytic cell. Which of the following is the anodic reaction? (A) Oxidation of Na + ions (B) Oxidation of Cl - ions (C) Reduction of Na + ions (D) Reduction of Cl - ions

Description : Chlorine gas is produced by the electrolysis of brine (NaCl solution with solid NaCl make up) in mercury electrolytic cell. Which of the following is the anodic reaction? (A) Oxidation of Na + ions (B) Oxidation of Cl - ions (C) Reduction of Na + ions (D) Reduction of Cl - ions

Last Answer : (B) Oxidation of Cl - ions

Pick out the correct statement. (A) Oxygen content decreases from lignite to bituminous coal as the coalification increases (B) The less the oxygen content, better is the coal, as it reduces the calorific value (C) With increase in oxygen content, moisture holding capacity of coal increases and the caking power decreases (D) All (A), (B) and (C)

Description : Pick out the correct statement. (A) Oxygen content decreases from lignite to bituminous coal as the coalification increases (B) The less the oxygen content, better is the coal, as it reduces the calorific value (C ... capacity of coal increases and the caking power decreases (D) All (A), (B) and (C)

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

Chlorination of water does not remove (A) Ammonia content (B) B.O.D. (C) Organic matter content (D) Dissolved oxygen

Description : Chlorination of water does not remove (A) Ammonia content (B) B.O.D. (C) Organic matter content (D) Dissolved oxygen

Last Answer : (D) Dissolved oxygen

Fluorosis (a bone disease) is caused by the presence of high concentration of __________ in atmospheric air. (A) Hydrocarbons (B) Hydrogen fluoride (C) Hydrogen sulphides (D) Nitrogen dioxide

Description : Fluorosis (a bone disease) is caused by the presence of high concentration of __________ in atmospheric air. (A) Hydrocarbons (B) Hydrogen fluoride (C) Hydrogen sulphides (D) Nitrogen dioxide

Last Answer : (B) Hydrogen fluoride

A carbonaceous fuel (containing no H2 or hydrocarbons) is burnt and the resulting flue gas contains 21% CO2 . It means that (A) 21% excess air has been used for combustion (B) 21% excess oxygen has been used for combustion (C) Complete combustion of fuel has taken place (D) No excess air has been used for combustion

Description : A carbonaceous fuel (containing no H2 or hydrocarbons) is burnt and the resulting flue gas contains 21% CO2 . It means that (A) 21% excess air has been used for combustion (B) 21% excess oxygen has ... (C) Complete combustion of fuel has taken place (D) No excess air has been used for combustion

Last Answer : (C) Complete combustion of fuel has taken place

Pick out the wrong statement. (A) Loamy soil is the best soil for vigorous plant growth, while the clayey soil is solid and hence the plant roots penetrate with difficulty (B) Large excess use of nitrogenous fertiliser in land causes the problem of diarrhoea and cyanosis (C) Application of large excess of Potassic fertiliser in soil increases the valuable carotene in fruits and vegetables (D) Cereal crops grown on alkaline soil absorb higher amount of fluorides thereby spreading fluorosis

Description : Pick out the wrong statement. (A) Loamy soil is the best soil for vigorous plant growth, while the clayey soil is solid and hence the plant roots penetrate with difficulty (B) Large ... vegetables (D) Cereal crops grown on alkaline soil absorb higher amount of fluorides thereby spreading fluorosis

Last Answer : (C) Application of large excess of Potassic fertiliser in soil increases the valuable carotene in fruits and vegetables

Washing of coal (A) Reduces its ash & sulphur content (B) Improves its coking properties (C) Increase the fusion point of its ash by removing chlorine compounds (D) All (A), (B) and (C)

Description : Washing of coal (A) Reduces its ash & sulphur content (B) Improves its coking properties (C) Increase the fusion point of its ash by removing chlorine compounds (D) All (A), (B) and (C)

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

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 : 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

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 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

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 sewage in river C. Solubility of oxygen in sewage is 95% of that of distilled water D. All the above

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

Last Answer : ANS: D

Pick up the correct statement from the following: A. In treated sewage, 4 ppm of D.O. is essential B. Only very fresh sewage contains some dissolved oxygen C. The solubility of oxygen in sewage is 95% that is in distilled water D. All the above

Description : Pick up the correct statement from the following: A. In treated sewage, 4 ppm of D.O. is essential B. Only very fresh sewage contains some dissolved oxygen C. The solubility of oxygen in sewage is 95% that is in distilled water D. All the above

Last Answer : ANS: D

When domestic sewage mixes with river water (a) small animals like rats will die after drinking river water (b) the increased microbial activity releases micronutrients such as iron (c) the increased microbial activity uses up dissolved oxygen (d) the river water is still suitable for drinking as impurities are only about 0.1%.

Description : When domestic sewage mixes with river water (a) small animals like rats will die after drinking  river water (b) the increased microbial activity releases  micronutrients such as iron (c) the increased ... (d) the river water is still suitable for drinking as  impurities are only about 0.1%.

Last Answer : (c) the increased microbial activity uses up  dissolved oxygen

The domestic sewage in large cities (a) has a high BOD as it contains both aerobic and anaerobic bacteria (b) is processed by aerobic and then anaerobic bacteria in the secondary treatment in Sewage Treatment Plants (STPs) (c) when treated in STPs does not really require the aeration step as the sewage contains adequate oxygen (d) has very high amount of suspended solids and dissolved salts.

Description : The domestic sewage in large cities (a) has a high BOD as it contains both aerobic and anaerobic bacteria (b) is processed by aerobic and then anaerobic bacteria in the secondary treatment in ... sewage contains adequate oxygen (d) has very high amount of suspended solids and dissolved salts.

Last Answer : (b) is processed by aerobic and then anaerobic bacteria in the secondary treatment in Sewage Treatment Plants (STPs)

Aerobic biological oxidation ponds used for the purification of polluted water (A) Destroys/removes pathogen from the sewage (B) Is not very effective for non-biodegradable substances (e.g. ABS) containing effluents (C) Destroys/removes pathogen much more effectively if the sewage is chlorinated (D) All (A), (B) & (C)

Description : Aerobic biological oxidation ponds used for the purification of polluted water (A) Destroys/removes pathogen from the sewage (B) Is not very effective for non-biodegradable substances (e.g. ABS) containing effluents (C) ... much more effectively if the sewage is chlorinated (D) All (A), (B) & (C)

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

Assertion: Sewage discharge in a water body causes eutrophication. Reason: This increases the organic content in water body and, hence, the growth of

Description : Assertion: Sewage discharge in a water body causes eutrophication. Reason: This increases the organic content in water body and, hence, the growth of

Last Answer : Assertion: Sewage discharge in a water body causes eutrophication. Reason: This increases the organic content ... Reason are false, then mark (4).

Turbidity of water is an indication of the presence of (A) Suspended inorganic matter (B) Dissolved solids (C) Floating solids (D) Dissolved gases

Description : Turbidity of water is an indication of the presence of (A) Suspended inorganic matter (B) Dissolved solids (C) Floating solids (D) Dissolved gases

Last Answer : (A) Suspended inorganic matter

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 : 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

Pick up the incorrect statement from the following: (A) Iron salts produce heavy flocks and hence remove more suspended matter (B) Iron salts remove hydrogen sulphides (C) Iron salts can be used over a limited range of pH values (D) Iron salts impart corrosiveness to water

Description : Pick up the incorrect statement from the following: (A) Iron salts produce heavy flocks and hence remove more suspended matter (B) Iron salts remove hydrogen sulphides (C) Iron salts can be used over a limited range of pH values (D) Iron salts impart corrosiveness to water

Last Answer : (C) Iron salts can be used over a limited range of pH values

Which one of the following tests employs Ethylene Diamine Tetra Acetic Acid as a titrating agent? (a) Chlorides (b) Dissolved oxygen (c) Hardness (d) Residual chlorine

Description : Which one of the following tests employs Ethylene Diamine Tetra Acetic Acid as a titrating agent? (a) Chlorides (b) Dissolved oxygen (c) Hardness (d) Residual chlorine

Last Answer : (c) Hardness

Which two gases are used to disinfect water in sewage treatment facilities? w) helium and nitrogen x) ozone and chlorine y) oxygen and hydrogen z) nitrogen and chlorine

Description : Which two gases are used to disinfect water in sewage treatment facilities? w) helium and nitrogen x) ozone and chlorine y) oxygen and hydrogen z) nitrogen and chlorine 

Last Answer : ANSWER: X -- OZONE AND CHLORINE

Ratio of primary air to secondary air increases with increase in the rank of coal, because the (A) High rank coals have higher amount of volatile matter (B) Ratio of fixed carbon to volatile matter increases (C) Oxygen content progressively decreases (D) Calorific value of the coal increases

Description : Ratio of primary air to secondary air increases with increase in the rank of coal, because the (A) High rank coals have higher amount of volatile matter (B) Ratio of fixed carbon to volatile matter increases (C) Oxygen content progressively decreases (D) Calorific value of the coal increases

Last Answer : (B) Ratio of fixed carbon to volatile matter increases

Sewage purification is performed by

Description : Sewage purification is performed by

Last Answer : Sewage purification is performed by A. Microbes B. Fertilizers C. Antibiotics D. Antiseptics

During purification process of sewage the gas given off, is A. Carbon dioxide B. Hydrogen C. Ammonia D. All the above

Description : During purification process of sewage the gas given off, is A. Carbon dioxide B. Hydrogen C. Ammonia D. All the above

Last Answer : ANS: D