Question 1
a. The kinds of material present in the wastewater are called _________
b. Water is used as a coolant in the _________
c. A septic tank is suitable for places having _________
d. _________ are the major cause of water pollution.
e. In an aerated tank_________ is decomposed.
f. The main sewer pipelines are called _________
g. Aerobic bacteria feed on organic matter and produce _________
h. The junction of the sewers from homes is called _________
i. The microorganisms which help in wastewater treatment settle at the bottom of the tank to form _________
j. The sludge from the settlement tank is shifted to another tank called _________
k. Large objects and garbage in the wastewater are removed by passing them through the _________
l. In the final step, the wastewater is treated with _________
m. The activity of bacteria on the sludge causes _________
n. The treatment of wastewater basically includes the removal of _________ Answer
Question 2
(Keywords : acrobic , organic , sludge , waster water treatment plant , earthworm , drainage, contaminants)
i. Vermicomposting toilets are ________________ to treat human waste.
ii. The full form of W WTP is _________________________________
iii. Cooking oil, fats should not be thrown in the ___________________ system directly, as they choke the pipes.
iv. _______________ bacteria consume human waste, food, water etc. in clarified water.
v. ____________ is decomposed by anaerobic bacteria.
vi. Urea is an ____________ impurity present in sewage.
vii. ____________________ is a term used for the undesirable substances present in water. Answer
i. earthworm
ii. waster water treatment plant
iii.drainage
iv. acrobic
v. sludge
vi. organic
vii. contaminants
Question 3
Write scientific terms for the following:-
i. Waste water released by homes, industries. Hospitals and offices ____________
ii. Impurities dissolves and suspended in waste water ________________
iii. Water that is safe for drinking ___________________
iv. Large, solid objects have to pass through which part in W WTP. ______________
Multiple Choice Questions
Question 4
Pick from the following one chemical used to disinfect water.
(a) Chlorine
(b) Washing soda
(c) Silica
(d) Coal
Question 5
Sewage is mainly a
(a) liquid waste.
(b) solid waste.
(c) gaseous waste.
(d) mixture of solid and gas
Question 6
Open drain system is a breeding place for which of the following.
(a) Flies
(b) Mosquitoes
(c) Organisms which cause diseases
(d) All of these
Question 7
Which of the following is not a source of waste water?
(a) Sewers
(b) Homes
(c) Industries
(d) Hospitals