CBSE Class 7 Science - MCQ and Online Tests - Unit 18 - Wastewater Story

CBSE Class 7 Science – MCQ and Online Tests – Unit 18 – Wastewater Story

 

Every year CBSE students attend Annual Assessment exams for 6,7,8,9,11th standards. These exams are very competitive to all the students. So our website provides online tests for all the 6,7,8,9,11th standards’ subjects. These tests are also very effective and useful for those who preparing for any competitive exams like Olympiad etc. It can boost their preparation level and confidence level by attempting these chapter wise online tests.

These online tests are based on latest CBSE syllabus. While attempting these, our students can identify their weak lessons and continuously practice those lessons for attaining high marks. It also helps to revise the NCERT textbooks thoroughly

CBSE Class 7 Science – MCQ and Online Tests – Unit 18 – Wastewater Story

Choose the correct answer:

Question 1.
Which one of the following is used in vermi-processing toilet?
(a) Earthworm
(b) Cockroach
(c) Both of these
(d) None of these

Answer

Answer: (a) Earthworm

---

Question 2.
Open drain system is a breeding place for which of the following:
(a) Files
(b) Mosquitoes
(c) Organisms which cause diseases
(d) All of these

Answer

Answer: (d) All of these

---

Question 3.
In sewerage manholes are located at every
(a) 20-25 m
(b) 50-60 m
(c) 90-100 m
(d) 100-110 m

Answer

Answer: (b) 50-60 m

---

Question 4.
Which one of the following is a step in wastewater treatment?
(a) Aeration
(b) Filtration
(c) Chlorination
(d) All of these

Answer

Answer: (d) All of these

---

Question 5.
Sludge in separate tanks is decomposed to get biogas by
(a) yeasts
(b) aerobic bacteria
(c) anaerobic bacteria
(d) none of these

Answer

Answer: (c) anaerobic bacteria

---

Question 6.
Which of the following is not a source of waste water?
(a) Sewers
(b) Homes
(c) Industries
(d) Hospitals

Answer

Answer: (a) Sewers

---

Question 7.
Which one of the following is a quality of wastewater?
(a) Foul smell
(b) Bad taste
(c) Dirty look
(d) All of these

Answer

Answer: (d) All of these

---

Question 8.
Sewage is mainly a
(a) liquid waste
(b) Solid waste
(c) gaseous waste
(d) Mixture of solid and gas

Answer

Answer: (a) liquid waste

---

Question 9.
Which of the following is/are products of wastewater treatment?
(a) Biogas
(b) Sludge
(c) Both Biogas and sludge
(d) Aerator

Answer

Answer: (c) Both Biogas and sludge

---

Question 10.
Period 2005-2015 is being celebrated as the international decade for action on
(a) water for life
(b) education for all
(c) global war
(d) terrorism

Answer

Answer: (a) water for life

---