Class 7 Waste Water Story CBSE Questions & Answers

Class 7 · Waste Water Story

This is Science Class 7 Waste water Story CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
Skimmer removes the
  • A
    Floatable solids like oil and grease
    Correct
  • B
    All the sewage parts
  • C
    Soluble wastes like alcohol
  • D
    Insoluble wastes like plastics
2
which of the following is a part of inorganic impurities of the sewage?
  • A
    pesticides
  • B
    treatment plant
  • C
    Urea
  • D
    Phosphates
    Correct
3
Sanitation in the cities is the function of
  • A
    Societies of locality
  • B
    Individual person
  • C
    Non-government organisation
  • D
    Municipal corporation
    Correct
4
Which is not an on site waste disposal system?
  • A
    Septic tank
  • B
    Chemical toilets
  • C
    Sewer system
    Correct
  • D
    Composting pits
5
The bacteria that require oxygen for respiration is called
  • A
    Anaerobic bacteria
  • B
    Vulnerable bacteria
  • C
    Bacillus bacteria
  • D
    Aerobic bacteria
    Correct
6
In a filtration plant water is filtered using layers of
  • A
    sand an fine gravel.
  • B
    sand and clay
  • C
    clay and fine gravel.
  • D
    sand , fine gravel and medium gravel
    Correct
7
Anaerobic bacteria is used for
  • A
    Respiration
  • B
    Regeneration
  • C
    Fragmentation
  • D
    Fermentation
    Correct
8
Water from bathroom, kitchen and toilet are called
  • A
    Unclean water
  • B
    Dirty water
  • C
    Waste water
    Correct
  • D
    Contaminated water
9
Process of removing pollutants before it enters a water body is called
  • A
    Sterilization of water
  • B
    Cleaning of water
    Correct
  • C
    Chlorination of water
  • D
    Purification of water
10
Inorganic substance present in sewage includes
  • A
    Nitrate and carbonates
  • B
    Carbonates and oxides
  • C
    Phosphates and oxides
  • D
    Nitrate and phosphates
    Correct
11
Network of big and small pipes called sewers join together to form
  • A
    Dig well
  • B
    Septic tank
  • C
    Bio-gas plant
  • D
    Sewerage
    Correct
12
The network of drainage pipe to carry waste water is called
  • A
    Drainage
  • B
    Waste water supply
  • C
    Sewer system
    Correct
  • D
    Water supply system
13
Chemical used for disinfecting water are
  • A
    Chlorine and hydrogen peroxide
  • B
    Nitrogen dioxide and Sulpher oxide
  • C
    Chlorine and ozone
    Correct
  • D
    Nitric acid and ozone
14
Waste water should be used after
  • A
    Removing solid wastes
  • B
    Removing pollutants
    Correct
  • C
    Adding manure
  • D
    Adding nutrients
15
which of the folloeing s not a source of wastewater?
  • A
    Homes
  • B
    Industries
  • C
    sewer
    Correct
  • D
    Hospitals