SSC JE 2019-20: Technical Quiz 89 for ESE & GATE CE Exams

Question 1

Consider the following statements

1) Relative stability of a sewage sample having 5-day incubation period at 37 ^oC is 68.44

2) Hydraulic loading capacity of high rate trickling filter is ten times of that of low rate trickling filter.

3) Activated sludge plant is a type of suspended growth system.

Which of the above statements are correct?

Question 2

Statement (I): Carbon monoxide affects oxygen carrying capacity of the human body.

Statement (II): Carbon monoxide is around 200 time more reactive than oxygen is with hemoglobin.

Question 3

How much bleaching powder (having 20% available chlorine) is needed to disinfect 10,000 litres of water whose chlorine demand is 1.0 mg/l? It should be ensured that, after about 1 hour contact time, 0.2 mg/l chlorine is available.

Question 4

Consider the following statements regarding pyrolysis:
1) It is an irreversible chemical change brought about by the action of heat in oxygen-free atmosphere.
2) Range of temperature is 500 °C to 1000 °C
3) Internal heating causes organic matter to decompose physically and chemically rather than burn.
4) It is a highly exothermic process.
Which of the above statements are correct?

Question 5

Assertion (A):the flow in water distribution pipes takes place due to gravity.
Reason (R): the flow in sewers takes place due to gravity.

Question 6

Statements (I):During an epidemic of infective hepatitis, the supplied water is super chlorinated.
Statements (II): Spore-forming bacteria which cause this disease are effectively removed form water by super chlorination.

Question 7

Assertion (A): Coagulation is the process of charge neutralization on colloids.
Reason (R): Flocculation is the process to grow the chargeless colloids into Settleable flocs.

Question 8

The figure below shows, BOD curve when the experiment was conducted at 20^oC. if the experiment is conducted at 30^oC, then the portion AB of the curve
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Question 9

Assertion (A): Composting is basically a treatment method for inorganic waste from a community.
Reason (R): In the incineration method of refuse disposal, the refuse is burnt off and the volume is much reduced..

Question 10

Consider the following statements regarding ecology:
(i) Climax ecosystem is a stage in the evolution of an ecosystem, at which all the species are in dynamic equilibrium among themselves as also with the environment
(ii) Ecological niche means all the physical, chemical and biological factors that a species needs in order to live and reproduce exist
(iii) Edge effect refers to the presence of rich and unique biological diversity found in an ecotone.
Which of the above statements are correct?