NCERT Solutions for Class 7 Science Chapter 18 Wastewater Story

Edited By Irshad Anwar | Updated on Feb 16, 2024 06:26 PM IST

Solution for Class 7th Wastewater Story is part of NCERT Solutions fo r Class 7 Science. A life without water is impossible. So it is our duty to avoid overuse or waste of water. What is sewage? How to treat polluted water? These questions are answered with the help of NCERT solutions for Class 7 Science Chapter 18 Wastewater Story. Terms like aeration, aerobic and anaerobic bacteria, biogas, etc. are explained in the chapter. The NCERT solutions for Class 7 Science Chapter 18 Wastewater Story help in the preparation of exams.

For Class 7th students who are following the NCERT syllabus, the NCERT Solutions (Class 6 to 12) for all the subjects help in their studies. NCERT Solutions for Class 7 Science Chapter 18 Wastewater Story gives an explanation to 12 exercise questions. Students are recommended to go through NCERT Solutions for Class 7 to score well in their examination. Waste water Story Class 7 Solutions provides answers to each question in the NCERT textbook. Scroll down to go through the questions and answers given in NCERT Solutions for Class 7 Science Chapter 18.

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NCERT Solutions for Class 7 Science Chapter 18 Wastewater Story Exercise:

Wastewater Story Class 7 Solutions:

1. Fill in the blanks:
(a) Cleaning of water is a process of removing ____________.
(b) Wastewater released by houses is called ____________.
(c) Dried ____________ is used as manure.
(d) Drains get blocked by ____________ and ____________.

Answer:

(a) Cleaning of water is a process of removing contaminants .
(b) Wastewater released by houses is called sewage .
(c) Dried cow dung is used as manure.
(d) Drains get blocked by plastic and fats .

Wastewater Story Class 7 NCERT Solutions:

2 . What is sewage? Explain why it is harmful to discharge untreated sewage into rivers or seas.

Answer:

Sewage is wastewater coming out of households, public places, farms and industry. It also includes rainwater which has flown into the sewers.

Untreated sewage contains harmful chemicals which if released directly into the rivers or seas would pollute them harming the ecosystem of the water bodies and making the water unfit for drinking or further use.

Class 7 Science Chapter 18 Question Answer:

3 . Why should oils and fats be not released in the drain? Explain.

Answer:

Oils and fats are insoluble in water. When released in the drain, it causes hardening and blocking of the sewage pipes. In an open drain, the fats block the soil pores which is required for filtering water. That is why oil and fats should not be released in the drain.

Class 7 Science Chapter 18 NCERT Solutions:

4 . Describe the steps involved in getting clarified water from wastewater.

Answer:

The treatment of wastewater includes the following steps:

(i) First, the physical waste like plastic, rags, pebbles, wood etc is removed by passing the water through a bar screen.

(ii) Then water is sent into sand removal tank for removing sand, pebbles, grit etc. through the process of sedimentation.

(iii) Then the rest of the solid waste is allowed to settle at the bottom of a large settling tank. This waste deposited at the bottom is called sludge and is removed through a scraper.

(iv) The harmful microorganisms in this water are killed through chlorination or UV rays.

(v) Through aerator, air is pumped into this water so that aerobic bacteria can grow and decompose any remaining organic wastes.

(vi) This treated water is then released into the water bodies.

Class 7 Wastewater Story NCERT Solutions:

5. What is sludge? Explain how it is treated.

Answer:

Sludge is the solid waste which has settled at the bottom of settling tanks during the process of wastewater treatment.

It is treated by decomposition by anaerobic bacteria. This activated sludge further can be used as manure.

Wastewater Story Class 7 Questions and Answers:

6 . Untreated human excreta is a health hazard. Explain.

Answer:

Untreated human excreta contains many harmful organisms which can cause lots of health-related problems. Untreated human excreta pollutes air, water and soil. Epidemics like cholera, meningitis etc. can be spread by untreated human excreta.

Class 7 Science Ch 18 Question Answer:

7 . Name two chemicals used to disinfect water.

Answer:

Two chemicals used to disinfect water are Chlorine and Ozone.

Class 7 Science Chapter 18 Solutions:

8. Explain the function of bar screens in a wastewater treatment plant.

Answer:

Bar screens filter most of the large-sized solid waste like plastic, cans, wood etc from wastewater.

Waste water Story Class 7 NCERT Solutions:

9. Explain the relationship between sanitation and disease.

Answer:

Sanitation refers to the availability of clean drinking water and proper treatment of human waste and sewage.

Without proper sanitation various diseases like cholera, typhoid, diarrhoea, etc. would spread and proper sanitation ensures that these diseases do not spread.

Chapter 18 Science Class 7 NCERT Solutions:

10 . Outline your role as an active citizen in relation to sanitation.

Answer:

As an active citizen, we should ensure that proper sanitation facilities are available in our home and workplaces, should make people aware about the necessity of sanitation and should not throw garbage in the open as it will block the drains and restrict the flow of the sewage.

Chapter 18 Science Class 7th Solutions:

11. Here is a crossword puzzle: Good luck!

Across
3 . Liquid waste products
4 . Solid waste extracted in sewage treatment
6 . A word related to hygiene
8 . The waste matter discharged from the human body
Down
1 . Used water
2 . A pipe carrying sewage
5 . Micro-organisms which causes cholera
7 . A chemical to disinfect water

Answer:

Across
3 . SEWAGE
4 . SLUDGE
6 . SANITATION
8 . EXCRETA
Down
1 . WASTEWATER
2 . SEWER
5 . BACTERIA
7 . OZONE

NCERT Solutions for Class 7 Science Chapter 18:

12. Study the following statements about ozone:

(a) It is essential for breathing of living organisms.
(b) It is used to disinfect water.
(c) It absorbs ultraviolet rays.
(d) Its proportion in air is about 3%.

Which of these statements are correct?
(i) (a), (b) and (c)
(ii) (b) and (c)
(iii) (a) and (d)
(iv) All four

Answer:

(ii) (b) and (c) are correct.

Wastewater Story Class 7 Science Chapter 18-Topics

Waste water Story
Water, Our Lifeline
What is Sewage
Water Freshness Up- Eventful Journey
Waste Water Treatment Plant (WWTP)
Better Housekeeping Practices
Sanitation And Diseases
Alternative Arrangement For Sewage Disposal
Sanitations In Public Places

NCERT Solutions for Class 7 Science Chapter 18 - Wastewater Story

The NCERT solutions for Class 7 Science Chapter 18 Wastewater Story make the preparation of the chapter easy. Students can make their studies interesting through activities. For example, by visiting a sewage treatment plant, students can know how practically the plant is running and can relate to what they have studied in the Science Chapter 18 Class 7.

Class 7th Chapter 18 Science NCERT Solutions helps in the preparation of the exam. The Waste water Story Class 7 NCERT Solutions give an explanation to all the 12 questions in the exercise. Students are recommended to go through NCERT Solutions for Class 7 Science to score high marks in their examination.

Chapter-wise NCERT Solutions of Class 7 Science

Chapter 1	Nutrition in Plants
Chapter 2	Nutrition in Animals
Chapter 3	Fibre to Fabric
Chapter 4	Heat
Chapter 5	Acids, Bases and Salts
Chapter 6	Physical and Chemical Changes
Chapter 7	Weather, Climate and Adaptations of Animals to Climate
Chapter 8	Winds, storms and cyclones
Chapter 9	Soil
Chapter 10	Respiration in Organisms
Chapter 11	Transportation in Animals and Plants
Chapter 12	Reproduction in Plants
Chapter 13	Motion and Time
Chapter 14	Electric Current and its Effects
Chapter 15	Light
Chapter 16	Water: A Precious Resource
Chapter 17	Forests: Our Lifeline
Chapter 18	Wastewater Story

NCERT Solutions for Class 7: Subject-wise

NCERT Solutions for Class 7 Maths

NCERT Solutions for Class 7 Science

Benefits of NCERT Solutions for Class 7 Science Chapter 18 Wastewater Story:

Class 7th Science Chapter 18 is important for the exam.
One of the main aims of Waste water Story Class 7 is to create awareness about water usage.
The NCERT Solutions for Class 7 Science Chapter 18 Wastewater Story help to understand the concepts studied in the chapter well.
Along with the NCERT Solutions of Class 7 Science Chapter 18 Wastewater theory, doing the activities mentioned in the chapter will add to the advantage of understanding the chapter in depth.
You will get all the answers to Science Chapter 16 Class 7 and it will help you score good marks in your school exam.
Class 7th Science Chapter 16 Question Answer will also help you to understand all the concepts easily.
You will get all the answers to Chapter 18 Science Class 7 and it will help you score good marks in your school exam.
Class 7th Science Chapter 18 Solutions PDF is easy to download and use offline.
Wastewater Story Class 7 questions and answers are prepared by subject experts as per the latest CBSE syllabus.

Also, Check NCERT Books and NCERT Syllabus here

We hope you will ace your examination with the help of NCERT Solutions for Class 7 Science Chapter 18 Wastewater Story.

Frequently Asked Questions (FAQs)

1. What is sewage class 7 ?

Sewage is a liquid containing waste that is disposed of in water by households, industrial, and agricultural activities. Hazardous elements and disease-causing organisms can be found in sewage.

2. What are the topics covered in NCERT Class 7 Science Chapter 18?

Here the topics are covered in NCERT Class 7 Science Chapter 18

Water, Our Lifeline
What is Sewage
Water Freshness Up- Eventful Journey
Waste Water Treatment Plant (WWTP)
Better Housekeeping Practices
Sanitation And Diseases
Alternative Arrangement For Sewage Disposal
Sanitations In Public Places

3. How many questions in NCERT Solutions for Class 7 Science chapter 18?

There are 12 questions in NCERT Solutions Class 7 Science chapter 18

4. What is sludge class 7 short answer?

When industrial or municipal wastewater is treated in a water treatment facility, a residual, semi-solid material known as sludge is created as a byproduct. The anaerobic bacteria break down sludge in a separate tank. Activated sludge is used as manure.

Also Read

NCERT Solutions for Class 7 Science Chapter 18 Wastewater Story

NCERT Solutions for Class 7 Science Chapter 17 Forests Our Lifeline

NCERT Solutions for Class 7 Science Chapter 16 Water A Precious Resource

NCERT Solutions for Class 7 Science Chapter 14 Electric Current and Its Effects

NCERT Solutions for Class 7 Science Chapter 13 Motion and Time

NCERT Solutions for Class 7 Science Chapter 12 Reproduction in Plants

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