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Right option is (d) 174

To explain: The CENTRAL pollution CONTROL BOARD and the department of ocean and environment has established 174 stations over the ENTIRE COASTAL line of the country.

Correct option is (d) 4

For explanation: Pollution enters into the water SYSTEM in four ways.

Run off, river flow transport, direct discharge of domestic and industrial waste and water sediment interface CAUSES the pollution.

Correct option is (b) Ganga action plan

Explanation: GAP stands for the Ganga action plan which is PROPOSED by the central POLLUTION CONTROL BOARD for monitoring the water bodies.

The correct option is (C) PHENOLS

Easiest explanation: The unpleasant odour of the water is due to the presence of the phenols, hydrogen SULPHIDES, chlorine and ORGANIC sulphur COMPOUNDS.

The correct option is (a) Increase efficiency

Explanation: Periodic CLEANING is NECESSARY to remove excess sludge in the WATER. So, it is USEFUL to increase the efficiency of the process.

Correct ANSWER is (a) Aerobic

Best explanation: DOMESTIC WATER treatment is CARRIED out in presence of the oxygen. The oxygen is taken from the water. So, it is aerobic PROCESS.

Right choice is (d) DRINKING

Easiest EXPLANATION: In drinking water some minerals MUST be present. In pharmaceuticals, cosmetics, explosives and in other manufacturing PROCESSES, the mineral FREE water is used.

The CORRECT answer is (b) No sludge formation

To explain I would SAY: In ion EXCHANGE process, there is no formation of sludge. So, it is CALLED as the CLEAN process.

Right CHOICE is (a) RAW water

To explain I would say: Raw water should be FREE of turbidity and suspended IMPURITIES as they are interfering in the exchange process.

The correct choice is (b) 5-15ppm

For explanation: The hardness of the WATER in the zeolite process can be TREATED at the range of the 5-15ppm. The REGENERATED zeolite can be used to REMOVE the calcium and magnesium ions from the water.

The correct CHOICE is (a) REGENERATED

For explanation: The exchange MEDIUM in the ZEOLITE process can be regenerated. Reagent USED in the lime soda process cannot be regenerated.

The CORRECT choice is (c) 20-25ppm

The best I can explain: The final HARDNESS of the WATER after treating by the hot LIME soda process is about the 20-25ppm. In very less time the water is treated in this method.

The correct choice is (a) 1%

To elaborate: 96% of the water is struck in the forms of oceans which is too saline to USE it directly and 2% is polar ICE caps and GLACIERS and 1% is under ground water.

The correct OPTION is (a) Detergents

To EXPLAIN: The detergents comes under the chemical MONITORING of the lake. Pathogens comes under the biological and the CONDUCTIVITY and turbidity comes under the PHYSICAL monitoring of the lake.

Correct choice is (c) 166

To explain I WOULD SAY: The BOD VALUE of domestic sewage is about 166ppm. Total quantity of ORGANIC matter utilised is called as the BOD.

The correct option is (a) More

To EXPLAIN: The initial EQUIPMENT in the ion exchange process is more. Continuous SUPPLY of softened WATER can be made available by providing storage FACILITIES.

Right choice is (b) LOW

The best I can explain: The capital cost of the ION EXCHANGE PROCESS is very high. The operational cost of the ion exchange process is about low.

The correct answer is (b) Mineral ACIDS

To EXPLAIN I would say: Lime soda PROCESS removes the mineral acids from the water. The cold soda lime, hot soda lime and continuous soda lime process are other processes to REMOVE the hardness.

The correct option is (b) SOFT WATER

The explanation is: The water which forms lather DIRECTLY with the soap is CALLED soft water. The water which forms precipitates when REACTED with soap is called as the hard water.

Right answer is (a) Wine RED

Easiest EXPLANATION: At the PH=10, the METAL DYE complex ion has the colour is wine red but the dye itself has the BLUE colour at the PH of 10.

Right OPTION is (d) Oxygen

The explanation: By providing the oxygen to the water in dry SEASON will REDUCE the POLLUTION of the RIVERS.

Right OPTION is (b) 4-8Hours

For explanation I would say: In biological OXIDATION PROCESS, depending on the organic LOAD, the oxidation process takes PLACE up to 4 to 8 hours. Organic impurities are reduced by the biological oxidation process by micro organisms.

Correct option is (d) Turbidity

To explain: The turbidity of the WATER COMES under the PHYSICAL MONITORING of the lake. TEMPERATURE, colour and solid also come under physical monitoring.

Right choice is (b) Typhoid

The explanation is: BACTERIA in water causes the typhoid. This includes a HIGH fever for the PERSON. Bacteria in water also CAUSE the cholera.

Right ANSWER is (B) Arsenic

Explanation: The arsenic POISONING water in Japan is from fishes where the industrial effluent was GOING into the sea containing arsenic.

The correct CHOICE is (C) 30-150ppm

The best I can EXPLAIN: The drinking water can have the magnesium LIMIT about 30-150ppm. The CALCIUM in the drinking water can be about 75-200ppm.

Right choice is (b) 0.74

To elaborate: Lime also reacts with BICARBONATES of Na and K to FORM CARBONATE. Since 100 parts of CaCO3 is equivalent to the 74 parts of Ca(OH)2. so, x=74/100=0.74.

Correct answer is (c) CELLULOSE acetate

For explanation I would say: The semi PERMEABLE membrane used in reverse OSMOSIS is cellulose acetate and cellulose butyrate etc.

Correct CHOICE is (d) FERMENTATION

For EXPLANATION: In anaerobic treatment, the organic ACID and alcohol is undergone into fermentation at 35^oC and the ppm of 5 to 6.

The correct ANSWER is (a) Temporary HARDNESS

The best I can explain: The hardness in the temporary hard WATER can be REMOVED by heating and filtrating the insoluble salts.

Right CHOICE is (c) 10

The best I can EXPLAIN: The buffer USED in the EDTA solution must have the PH of 10. Freshly prepared solutions are more affective to have the ACCURATE results.

The correct option is (d) 0.1-1ppm

To ELABORATE: The IRON is about the range in drinking WATER is 0.1-1.0ppm. The magnesium is about the range of 30-150ppm in drinking water.

Correct option is (b) Automatic sensors

Easy EXPLANATION: By using the automatic sensors, the MONITORING SYSTEMS becomes more easier. Turbines are used to generate electricity.

Correct ANSWER is (a) Soil EROSION

Easiest EXPLANATION: A large amount of soil can move with the run off called as soil erosion. When the rain fall occurs, with the WATER, the top layer of the soil also moves.

Correct answer is (a) 0.2 to 1

To ELABORATE: The organic matter has the desired limit in WATER about 0.2 to 1 ppm. INCREASE in the value indicates the POLLUTION.

Right CHOICE is (b) Increase in pollution

The BEST explanation: Increase in the VALUE of the BOD in water indicates the increase in the water pollution.

Correct choice is (a) High

Best EXPLANATION: The cost of the RESINS used in the ion exchange process is high and the REGENERATION of the resins in also a costly process.

Correct ANSWER is (a) 2

To explain I would say: There are two types of methods. They are: By absorbing the radio ACTIVE elements by USING suitable absorbent. Allowing of such periods at which it SEPARATES from WATER.

Right choice is (B) Costlier

The best I can explain: The one of the DISADVANTAGES of the ion exchange PROCESS is the REGENERATION of the acids and ALKALIS in ion exchange process is costlier.

Right option is (c) Carbondioxide

To elaborate: The dissolved carbondioxide is not REMOVED during the zeolite or the PERMUTIT’s process. It can be removed in the LIME soda process.

Right option is (c) Corrosion of boiler

Explanation: DUE to heating at high temperature in the hot lime SODA PROCESS reduces the corrosion of boilers. The heating is done to REMOVE the DISSOLVED gases in the water.

Right answer is (b) Detergents

Best explanation: The bad odour of water is DUE to the phenols, decaying ORGANIC MATTER and phenols. The peculiar odour is due to the detergents and pesticides.