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.
Related Mcqs:
- Presence of H2S in raw water (to be chlorinated) results in the_____________________?
A. Reduced softening capacity of zeolite
B. Increased dosage of chlorine to provide a disinfecting residual in the water
C. Easy removal of its hardness
D. None of these - Exothermic condensation reaction of monochlorobenzene with chloral in presence of 20% oleum as catalyst produces DDT. The reaction temperature is maintained at _____________ °C ?
A. 15-30
B. 90-100
C. 250-300
D. < 0 - Platinum is a versatile catalyst for many processes in chemical industries. It is highly prone to be poisoned by the presence of_________________?
A. Carbon
B. Arsenic
C. Lead
D. Sulphur - Sulphur removal by heating of pyrite ore in presence of air is called its ____________________?
A. Reduction
B. Roasting
C. Calcination
D. Smelting - Liquor poisoning generally occurs due to the presence of _________________ in it ?
A. Ethyl alcohol
B. Impurities
C. Methyl alcohol
D. Carbonic acid - Oxidation of ortho-xylene in presence of ______________ catalyst is done to produce phthalic anhydride on commercial scale ?
A. Nickel
B. Vanadium
C. Alumina
D. Iron - Ethylene oxide is produced by oxidation of ethylene in presence of AgO catalyst at __________________?
A. 1 atm & 100°C
B. 5 atm & 275°C
C. 100 atm & 500°C
D. 50 atm & 1000°C - The metallic aluminium is obtained from pure alumina in the presence of fused cryolite by_________________?
A. Electrolysis
B. Electrolytic reduction
C. Electrolytic oxidation
D. None of these - Presence of sodium tripolyphosphate (an additive) in synthetic detergent___________________?
A. Facilitates its use even in hard water (by sequestering the water-hardening Ca & Mg ions)
B. Inhibits its corrosive effects
C. Does not allow redeposition of dirt on the cleaned surface
D. None of these - Permanent hardness of water is due to the presence of calcium & magnesium __________________?
A. Bi-carbonates
B. Sulphates & chlorides
C. Carbonate
D. None of these
