Quiz: Civil Engineering
Topic: ENVIRONMENT ENGINEERING
Each question carries 1 mark
Negative marking: 1/4 mark
Time: 8 Minutes
Q1. Which one of the following pairs is INCORRECTLY matched?
(a) Air Valve – to check the water flow in pipes, in the directions
(b) Check valve – To release the accumulated air in pipelines.
(c) Scour valve – To drain or empty the pipe line section
(d) Surge arrestor – control of water hammer in pipe lines
Q2. Which of the following are primary air pollutants?
(a) Sulphur dioxide and Nitrogen oxides
(b) Ozone and Carbon monoxide
(c) Sulphur dioxide and ozone
(d) Nitrogen oxide and ozone
Q3. Pollutant Standards Index (PSI) value in between 101 – 199 denotes the air quality as…………
Q4. Acid rains are caused by the following pollutants: –
(a) SO₂ and O₃
(b) SO₂ and NO_x
(c) NO_x and O_3
(d) CO and SO₂
Q5. Greenhouse effect of CO₂ is_______:
(a) permitting the outside solar radiation to reach the ground but preventing terrestrial radiation from the ground into the space
(b) Permitting the solar radiation of short length and reradiated terrestrial heat of long wave length
(c) reflecting the heat rays into the space thereby keeping the temperature of earth unaffected
(d) Causing absorption of heat troposphere and thereby decreasing the temperature of earth with increase in CO₂ concentration
Q6. A waste water sample of 2 ml is made upto 300 ml is BOD with distilled water Initial DO of the sample is 8mg/l and after 5 days it is 28mg/l. What is its BOD?
(a) 894 mg/l
(b) 900 mg/l
(c) 300 mg/l
(d) 1200 mg/l
Sol. Check value or reflux valve or non-returning valves are allows the flow only in one direction only back flow is not permitted.
Sol. Primary pollutants-
Sulphur dioxide (SO_2 )
Nitrogen oxide (NO) & (NO_2 )
Carbon mono oxide (CO)
Radio active substance
Secondary pollutants –
Ozone (O_3 )
Peroxyacetyl nitrate (PAN)
Sol. the main cause of acid rain is Sulphur oxides (SO_x ) and Nitrogen oxides (NO_x ).
Sol. Given, volume of diluted sample = 300 ml.
Initial volume of test sample = 2 ml.
Initial dissolved oxygen (DOi)= 8 mg/l
Final dissolved oxygen (DO_F)= 2 mg/l.
▭(BOD=(DOi-DO_F )×Dilution factor)
Dilution factor = (volume of diluted sample)/(Initial volume of test sample)
BOD= (8-2) ×150
= 900 mg/l.