CBSE Class 8 - Science - Ch 18 Pollution Of Air and Water - Chapter Notes (#cbseNotes)

POLLUTION OF AIR AND WATER

(Chapter Notes)

Pollution is release of harmful substances in the environment thus causing threats to our ecosystem. Even non-harmful substances when precipitated in environment can be harmful. Land, water and air are the most important natural resources. Man made factors (agriculture, industrialization, transport etc.) are the primary reasons for the pollution.

According to World Health Organizations, five millions deaths occur in India due to pollution.

Pollution can be classified in many categories like:

• Land Pollution
• Air Pollution
• Water Pollution
• Noise Pollution
• Light Pollution

Here we discuss primarily about Air pollution and Water pollution.

Composition of Air

Air is a mixture of gases. 

By volume, Nitrogen:78%, Oxygen:21% and 1% (remaining gases like Carbon Di-oxide, Ozone, Argon, Methane etc.)

CBSE Class 6 -10 - English Grammar - Practice Jumbled Up Sentences (#cbseNotes)

 Practice Jumbled Up Sentences

Try online exercise

Jumbled Up Sentences or Rearrange words to form meaningful and grammatically correct sentence. These questions are pretty common in question papers.

You may try the following links to practice this exercise.

English Vocabulary - Single Word Substitutions (#cbseNotes)

English Vocabulary - Single Word Substitutions

1. Shy, timid, unwilling to face a situation

2. One who gives direction from behind the scene on a stage

3. One who gets pleasure in others trouble and pain

CBSE Class 10 - Biology - Heredity and Evolution - Origin Of Life On Earth (Concept Points) (#cbseNotes)

Origin Of Life On Earth (Concept Points)

① Most scientists believed that life arose from nonliving matter, mostly from gases. It originated in primitive form in the oceans of the earth.

② 4 billion years ago, the primitive atmosphere was formed. It had little oxygen and was likely thick with water vapor, along with compounds released by volcanic eruptions, such as nitrogen oxides, carbon dioxide, methane, ammonia, and hydrogen.

CBSE Class 12 - English - Flamingo - Ch1 - The Last Lesson (Question Bank) (#cbseNotes)

Lesson 1 - The Last Lesson (Question Bank)

Short Questions

1. Give 2 reasons why Franz thought of running away and spending the day out of doors?

2. What was more tempting than the rule of participles?

3. What was the bulletin board famous for?

4.  Describe the usual scene and how was it different that day?

5.  Describe the appearance of the master M. Hamel that day?

CBSE Class 10 - French - Periodic Test Paper 2 - (2017-18) (#cbsePapers)

CBSE Class 10 - French -
Periodic Test Paper 2 - (2017-18)

CBSE Class 10 - Maths - Periodic Test Paper 2 - (2017-18) (#cbsePapers)

CBSE Class 10 - Maths -
Periodic Test Paper 2 - (2017-18)

CBSE Class 10 - Science - Periodic Test Paper 2 - (2017-18) (#cbsePapers)

CBSE Class 10 - Science - Periodic Test Paper 2 - (2017-18)

CBSE Class 10 - Social Science - Periodic Test Paper 2 - (2017-18) (#cbsePapers)

CBSE Class 10 - Social Science - Periodic Test Paper 2 - (2017-18)

CBSE Class 6 / Class 7 - English Grammar - To vs Too vs Two (Worksheet) (#cbseNotes)

To vs Too vs Two
(English Grammar Worksheet)

Remember:
To is a function word used along with a verb, Or used as a preposition
Too means 'also' or 'excessive'
Two is a number (2)

Fill in each sentence with the correct word.

1. I am going __________ read a book.

2. Meena ran __________ kilometers.

3. Is Sakshi coming __________ ?

4. She got __________ wrong on the test.

5. My brother likes __________ play football.