A standard test for determination of hardness in water is termed as ______________ test?

A. Smoke
B. Powder
C. Grit
D. Aggregates

A. By chemical coagulation
B. In sedimentation tanks equipped with mechanical scrapper
C. In vacuum filter
D. In clarifiers

A. ‘Green house’ (made of glass) allows visible sunlight (i.e., short wavelength solar radiation
like ultra-violet rays) to pass through the glass and heat up the soil thereby warming up plants
inside it
B. The emitted longer wavelength radiation (e.g., infrared) is partly reflected and partly absorbed
by the glass of the green house
C. ‘Green house effect’ in earth’s atmosphere is due to increasing CO2 level in atmosphere, where
CO2 acts like the glass of ‘green house’ thereby warming up the earth’s surface
D. ‘Green house’ is colder than the outside atmosphere

A. Packed scrubber
B. Gravity settling chamber
C. Electrostatic precipitator
D. Hydrocyclone

A. 10 to 20
B. 100 to 200
C. 1500 to 2500
D. 4000 to 5000

A. Reduction in its dissolved oxygen content
B. Discoloration of bathroom fixtures
C. Temporary hardness
D. None of these