Description : In slow sand filters, the turbidity of raw water can be removed only up to (A) 60 mg/litre (B) 75 mg/litre (C) 100 gm/litre (D) 150 mg/litre
Last Answer : (A) 60 mg/litre
Description : Rapid gravity filter can only remove turbidity of water upto (A) 15 to 25 gm/litre (B) 25 to 30 gm/litre (C) 30 to 35 cm/litre (D) 35 to 40 gm/litre
Last Answer : (D) 35 to 40 gm/litre
Description : The yield of a rapid gravity filter as compared to that of slow sand filter, is (A) 10 times (B) 15 times (C) 20 times (D) 30 times
Last Answer : (D) 30 times
Description : Efficiency of removing bacterias from raw water by a slow sand filter, is (A) 80% to 81% (B) 85% to 86% (C) 90% to 97% (D) 98% to 99%
Last Answer : (D) 98% to 99%
Description : In a rapid sand filter, air binding is caused due to excessive (A) Negative pressure (B) Pressure (C) Turbidity (D) Water pressure
Last Answer : (A) Negative pressure
Description : A slow sand filter is cleaned if its filter head is higher than (A) 10 cm to 20 cm (B) 20 cm to 40 cm (C) 40 cm to 70 cm (D) 70 cm to 120 cm
Last Answer : (D) 70 cm to 120 cm
Description : Pick out the true statement pertaining to water treatment. (A) Slow sand filters can remove colour completely (B) Activated carbon can be used for taste & odour control without subsequent filtration ... of water (D) Normally, the turbidity is removed by adding a coagulant prior to sedimentation
Last Answer : (D) Normally, the turbidity is removed by adding a coagulant prior to sedimentation
Description : Standard unit of turbidity of water is in one litre of distilled water, one milligram of finely divided (A) Silica (B) Mud (C) Clay (D) Organic matter
Last Answer : (A) Silica
Description : Water filtration rate in a slow sand filter ranges from __________ litres/m2 /hr. (A) 10 to 20 (B) 100 to 200 (C) 1500 to 2500 (D) 4000 to 5000
Last Answer : (B) 100 to 200
Description : The period of cleaning of a slow sand filter, is usually (A) 5 to 10 days (B) Two weeks to three weeks (C) One month to three months (D) Three months to six months
Last Answer : (C) One month to three months
Description : A high velocity of wash water is required for (A) Rapid gravity filter with strainers (B) Rapid gravity filter without strainers (C) Slow sand filter with strainers (D) Slow sand filter without strainers
Last Answer : (B) Rapid gravity filter without strainers
Description : Distribution of wash water is provided in (A) Sedimentation tank (B) Slow sand filter (C) Rapid gravity filter (D) All the above
Last Answer : (C) Rapid gravity filter
Description : After cleaning a slow sand filter, the filtered water is not used for (A) 6 hours to 12 hours (B) 12 hours to 18 hours (C) 18 hours to 24 hours (D) 24 hours to 36 hours
Last Answer : (D) 24 hours to 36 hours
Description : Pick up the incorrect statement from the following: (A) The water entering the slow sand filters should be treated by 9.386 coagulants (B) The depth of water on the filter should be twice the ... is 0.75 times the depth of filter sand, the water obtained is purest (D) All the above
Last Answer : (D) All the above
Description : Rate constant for a first order reaction does not depend upon reaction time, extent of reaction and the initial concentration of reactants; but it is afunction of reaction temperature. In a chemical reaction, the time required to ... Then the order of this reaction is: (A) 0 (B) 1 (C) 2 (D) 3
Last Answer : (B) 1
Description : Rapid sand filter (A) Should be preceded by coagulation and sedimentation (B) Uses rapid sand as filter media (C) Is used after slow sand filtering has been done (D) Can combine disinfection also
Last Answer : (A) Should be preceded by coagulation and sedimentation
Description : Turbidity of raw water is a measure of (A) Suspended solids (B) Acidity of water (C) B.O.D. (D) None of these
Last Answer : (A) Suspended solids
Description : Dust content in raw blast furnace gas is about __________ gm/Nm3 ; hence it is cleaned to the dust level of about < 10 mg /Nm3 before use. (A) 15-30 (B) 1-2 (C) 70-100 (D) 150-200
Last Answer : (A) 15-30
Description : The bed slope in slow sand filters, is generally kept (A) 1 in 50 (B) 1 in 75 (C) 1 in 100 (D) 1 : 200
Last Answer : (C) 1 in 100
Description : Ammonia content in raw coke oven gas is about __________ gm/Nm3 . (A) 1 (B) 5 (C) 50 (D) 100
Last Answer : (B) 5
Description : Rapid gravity filters (A) Were developed by G.W. Fuller (B) Make use of coarser sand with effective size as 0.5 mm (C) Yield as high as 30 times the yield of slow sand filters (D) All the above
Description : Molarity is defined as the number of gm moles of solute per __________ of solvent. (A) Litre (B) kg (C) gm (D) c.c
Last Answer : (A) Litre
Description : Molality is defined as the number of gm moles of solute per __________ of solvent. (A) Litre (B) gm (C) Kg (D) m
Last Answer : (C) Kg
Description : For the reaction as shown in the bellow figure, the rate of formation of Z is 0.2 gm mole/litre.hr. What is the rate of disappearance of X in gm mole/litre.hr? (A) 0.4 (B) 0.1 (C) 0.2 (D) None of these
Last Answer : (A) 0.4
Description : The maximum permitted loss of head in a rapid sand filter, is (A) 1 m (B) 2 m (C) 3 m (D) 4 m
Last Answer : (C) 3 m
Description : . Dechlorination of treated water is necessary to (A) Remove residual turbidity (B) Reduce the bacterial load on filter (C) Control taste and odour (D) Remove chlorinous taste
Last Answer : (D) Remove chlorinous taste
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 : COD of raw municipal sewage may be in the range of about __________ mg/litre. (A) 1-2 (B) 5-10 (C) 90-120 (D) 1500-2500
Last Answer : (C) 90-120
Description : Water filtration rate in a rapid sand filter ranges from __________ kilolitres/m2 /hr. (A) 0.1 to 1 (B) 3 to 6 (C) 10 to 15 (D) 15 to 20
Last Answer : (B) 3 to 6
Description : An identified source of irrigation water has ion concentrations of Na+ , Ca++ and Mg++ as 20, 10 and 8 milliequivalents per litre, respectively. The SAR of this water is approximately : a) 2.06 b) 6.67 c) 2.67 d) zero
Last Answer : b) 6.67
Description : A healthy person eats the following diet-5 gm raw sugar, 4 gm albumin, 10 gm pure buffalo ghee adultrated with 2 gm vegetable ghee (hydrogenated vegetable oil) and 5 gm lignin. How many calories he is likely to get? (a) 126 (b) 164 (c) 112 (d) 144
Last Answer : (d) 144
Description : If 4 gm of a radioisotope has a half life period of 10 days, the half life of 2 gm of the same isotope will be __________ days. (A) 5 (B) 10 (C) 20 (D) 30
Last Answer : (B) 10
Description : To prevent movement of moisture from sub-grade to road pavement on embankments about 0.6 m to 1 m higher than water table, the thickness of cut off layer of coarse sand used, is (A) 15 cm (B) 20 cm (C) 30 cm (D) None of these
Last Answer : Answer: Option D
Description : a rapid gravity filter (A) Raw water from the source is supplied (B) Disinfected raw water is supplied (C) Raw water passed through coagulation tank is supplied (D) None of these
Last Answer : (C) Raw water passed through coagulation tank is supplied
Description : The net pressure gradient that causes the fluid to filter out of the glomeruli into the capsule is (a) 50 mm Hg (b) 75 mm Hg (c) 20 mm Hg (d) 30 mm Hg.
Last Answer : c) 20 mm Hg
Description : Consider the following statements. The role of the gravel bed in a rapid sand filter is : 1. To filter out large suspended matter 2. To support the sand bed above it 3. To prevent the escape of sand particles 4. To uniformly ... and 5 b) 2, 3 and 4 only c) 3, 4 and 5 only d) 1, 2 and 3 only
Last Answer : b) 2, 3 and 4 only
Description : Maximum permissible turbidity in potable water is __________ ppm. (A) 1 (B) 10 (C) 250 (D) 1000
Description : Littoral drift (A) Is the raised line of sand, parallel to the sea coast (B) Is the slow movement of surface water at sea caused by the wind (C) Is a current parallel to the shore, caused due to tangential component of the wind (D) Is a current perpendicular to the shore line caused due to wind
Last Answer : (C) Is a current parallel to the shore, caused due to tangential component of the wind
Description : The commonly used raw material in the manufacture of cement, is (A) Slate (B) Sand stone (C) Lime stone (D) Basalt
Last Answer : Answer: Option C
Description : The dimensions of a 35 litre forma for measuring aggregates by volume, are: (A) length 30 cm, breadth 25 cm, height 30 cm (B) length 39 cm, breadth 25 cm, height 32 cm (C) length 27 cm, breadth 27 cm, height 48 cm (D) length 220 cm, breadth 25 cm, height 40 cm
Description : To prevent movement of moisture from sub-grade to road pavement at the same level as that of water-table, thickness of a cut off layer of coarse sand, is (A) 15 cm (B) 20 cm (C) 30 cm (D) 45 cm
Last Answer : Answer: Option A
Description : Mud balls may be removed by (A) Breaking and washing (B) Washing the filter with a solution of caustic soda (C) Removing, cleaning and replacing the damaged sand (D) All the above
Description : The U.C. (uniformity coefficient) D60/D10 for the best filter media sand should be (A) 2 (B) 3 (C) 4 (D) 5
Last Answer : (A) 2
Description : If aggregates completely pass through a sieve of size 75 mm and are retained on a sieve of size 60 mm, the particular aggregate will be flaky if its minimum dimension is less than (A) 20.5 mm (B) 30.5 mm (C) 40.5 mm (D) 50.5 mm
Description : The maximum permissible hardness for public supplies is (A) 95 mg/litre (B) 105 mg/litre (C) 115 mg/litre (D) 125 mg/litre
Last Answer : (C) 115 mg/litre
Description : If the average daily demand of a city of 50,000 population, is 20 m.l.d., the maximum daily demand is (A) 24 mld (B) 30 mld (C) 36 mld (D) 54 mld
Last Answer : (C) 36 mld
Description : The unit of filter medium resistance is (A) cm-1 (B) gm/cm-1 (C) cm/gm-1 (D) gm-1
Last Answer : (A) cm-1
Description : Registered newspaper single copy (max 5 kg) rate is a) Up to 50 gm- 0.25 b) Exceeding 50 gm to 100gm-0.50 c) Addl 100gm- 0.20 d) All the above are correct
Last Answer : d) All the above are correct
Description : The haemoglobin content per 100 mL of blood of a normal healthy human adult is (a) 5 - 11 gm (b) 25 - 30 gm (c) 17 - 20 gm (d) 12 - 16 gm.
Last Answer : (d) 12 - 16 gm.